JP2002130022A - Internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make compatible both deposit restraint in an injection nozzle of an injector and excellent fuel consumption. SOLUTION: A micro-computer 21 brings an operation parameter to a value of moderate combustion, e.g. a timing lag side when in ignition timing, in accordance with lowering of an engine speed detected by an engine speed detecting sensor 301, i.e., in accordance with prolongaion of an injection interval, restrains solidification (depodit formation) of a liquid phase component by heating when the injection interval is long to bring the condition where fuel existing in the injector injection nozzle is evaporated during the interval easy to leave depositingly only the liquid phase component, and conducts fast combustion when the injection interval is short to bring the condition where the deposit of the liquid phase component is not allowed to progress excessively and washed away by the next injection. The deposit restraint and the excellent fuel consumption are made compatible by conducting moderate combustion where the deposit is hardly generated, only in the operation condition where deposit generating conditions are all present.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for reducing deposits on an injector of an internal combustion engine.

[0002]

2. Description of the Related Art Deposits adhering and accumulating in an injection hole of an injector of an internal combustion engine are formed by evaporating a portion of fuel remaining in the injection hole after stopping fuel injection, and heating the remaining liquid phase component. It is known that they have been solidified. The solidification of the fuel proceeds by the deposition precursor contained in the liquid phase component causing a dehydrogenation reaction or a polymerization reaction. As a result, the cross-sectional area of the injection hole decreases with the accumulation of the deposit, and the fuel injection flow rate decreases.

[0003] In the case of an in-cylinder injection type internal combustion engine, the tip of the injector is exposed to a high temperature due to the heat of combustion of the fuel in the combustion chamber. It is desirable to use a high material. However, since the valve body constituting the valve mechanism is required to have a considerable degree of durability at the distal end, the range of material selection is narrow, and compatibility with the thermal conductivity is difficult. Therefore, as in the technique described in Japanese Patent Application Laid-Open No. 9-287525, the temperature of the engine body is detected, and when the detected temperature is high, the operating parameters for controlling the engine body are set so that the combustion in the combustion chamber becomes slow. In some cases, the temperature at the tip of the injector is made to work in a direction in which the temperature at the tip of the injector decreases, for example, by preventing the temperature at the tip of the injector from excessively rising by retarding the ignition timing, and suppressing the accumulation of deposits. Is being planned. Japanese Patent Application Laid-Open No. 9-264232 discloses that deposits can be satisfactorily suppressed by keeping the temperature of the injection hole lower than the 90% distillation temperature of the fuel used.

[0004]

However, if the operating parameters of the internal combustion engine are determined only for the purpose of reducing the deposit, there is a possibility that the operating performance of the internal combustion engine, such as fuel efficiency, may be reduced.

[0005] The present invention has been made in view of the above circumstances,
An object of the present invention is to provide an internal combustion engine that can reduce the deposit while maintaining the operation performance of the internal combustion engine.

[0006]

According to the present invention, if the time interval between the injection of the injector and the next injection of the injector is short, the degree of evaporation of the fuel is small even if the temperature of the tip of the injector is considerably high. The present invention is based on the knowledge of the inventors that the deposition of deposits is suppressed and the decrease in the flow rate of fuel in the injection holes can be suppressed. Operating state detecting means for detecting the operating state of the engine main body, based on the detected operating state; In an internal combustion engine provided with operating parameter setting means for setting an operating parameter for control, the operating state detecting means includes an operating parameter detecting means for controlling the operating parameters based on the injection of the injector. Time interval detecting means for detecting a time interval until the next injection of the injector, wherein the operating parameter setting means sets the operating parameter such that the longer the detected time interval, the lower the temperature of the combustion chamber. Set so that

When the time until the next injection is long and it is really necessary to prevent the deposition of deposits, the temperature in the combustion chamber shifts to a lowering direction. The shorter the time until the next injection, the more the operating parameters become. Values that increase the temperature in the combustion chamber are allowed. Therefore, the driving efficiency is high and the deposit can be suppressed.

According to the invention of claim 2, in the configuration of the invention of claim 1, the time interval detecting means is constituted by an engine rotation detecting means so that the time interval can be determined based on the engine rotation.

Since the fuel injection is performed substantially in synchronization with the engine speed, the higher the engine speed, the shorter the time interval between the injection of the injector and the next injection of the injector.
That is, the length of the time interval is known from the engine speed. The engine speed indicates a basic operation state of the internal combustion engine, and has conventionally been a basic operation parameter in controlling the engine body. Therefore, it is not necessary to newly provide a time interval detecting means.

According to a third aspect of the present invention, in the configuration of the first or second aspect, the engine body is provided with cooling water temperature detecting means for detecting a temperature of cooling water for cooling the engine body. The operating parameter setting means, the higher the detected cooling water temperature, the operating parameter,
The temperature is set so as to decrease the temperature in the combustion chamber.

The higher the cooling water temperature, the more the operating parameters change in the direction of decreasing the temperature in the combustion chamber. The temperature condition of the engine body varies depending on the operating conditions.If the engine body is in a "cold" state, for example, in a cold start, the heat removal ability is sufficient, so rapid combustion that raises the combustion chamber temperature is allowed. As a result, the operation efficiency is high, and the deposit can be suppressed.

According to a fourth aspect of the present invention, in the configuration of the first to third aspects of the present invention, there is provided a temperature detecting means for detecting a temperature of a tip end portion of the injector, and the operating parameter setting means comprises: The operating parameter is set such that the higher the temperature at the tip end of, the lower the temperature in the combustion chamber.

[0013] The higher the injector tip temperature, the more the operating parameters change in the direction of decreasing the temperature in the combustion chamber.
Therefore, even if the injector tip temperature tends to increase due to aging or the like, the operating parameters will follow this to give an appropriate temperature in the combustion chamber,
Further, the driving efficiency is high, and the deposit can be suppressed.

According to a fifth aspect of the present invention, in the internal combustion engine according to the fourth aspect, a plurality of injectors are provided so as to correspond to a plurality of cylinders on a one-to-one basis.
Among the plurality of injectors, a configuration is provided in which the temperature of the tip of the injector, which has the highest tendency to increase in temperature, is substantially detected.

Since the operating parameters are set based on the temperature at the tip of the injector, which tends to be the highest in temperature, it is possible to provide a good deposit adhesion suppressing effect for all cylinders without providing temperature detecting means for all cylinders. Obtainable.

According to a sixth aspect of the present invention, in the configuration of the first to fifth aspects, the engine body is provided with cooling water temperature adjusting means for adjusting the temperature of the cooling water, and the cooling water temperature adjusting means is provided. The control means is configured to set the cooling water temperature to a preset target temperature when the detected time interval is longer than a preset time threshold value.

For example, when the engine body is heated,
If the time interval between the injection of the injector and the next injection of the injector is long, it can be said that deposits are likely to adhere, but in this case, the cooling water is adjusted to the target temperature, so the engine body including the tip of the injector is The temperature also moves in the suppression direction, and the deposition of the deposit is suppressed. Since the engine body temperature is not lowered, the operation efficiency is not lowered.

According to a seventh aspect of the present invention, in the configuration of the first through sixth aspects, the engine body has a tip end portion of the injector protruding into the combustion chamber, and directly injects fuel from the injection hole into the combustion chamber. In-cylinder injection type.

In an in-cylinder injection type internal combustion engine, the present invention is particularly preferable because the injector tip is exposed to high-temperature combustion gas.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) FIGS.
1 shows an internal combustion engine of the present invention. The internal combustion engine will be described below for powering a vehicle. The engine body 1 of the internal combustion engine is a four-cylinder in-cylinder injection type, not shown,
Each cylinder has four intake valves and two exhaust valves.
It has a valve structure, and the injectors 11A, 11
B, 11C and 11D are provided.

FIG. 2 shows an attached state of the injector. Although only the injector 11B is shown,
The injectors 11A, 11C, and 11D have the same structure as the injector 11B. The injector 11B includes a cylinder head 10 that covers a cylinder block (not shown).
1 and the front end 111 is
Is facing inside. The injector 11B has a general configuration of a solenoid type, in which a needle is disposed in a nozzle into which fuel is introduced, and a spring for allowing the needle to sit on a seat formed in a valve body, and a needle behind the needle. And a solenoid for releasing the seat. By energizing the solenoid, the armature integrated with the needle is sucked, the needle is unseated, and fuel is injected from the injection hole 112 formed at the tip of the nozzle portion, forming an air-fuel mixture with the intake air.

The ignition of the air-fuel mixture is performed by using ignition coils 12A, 12B, 12C,
This is performed by energizing 12D.

The engine body 1 also includes a fuel pressure control actuator 13, a valve timing actuator 1
4. A swirl actuator 15 is provided. The fuel pressure control actuator 13 is constituted by a pump whose discharge amount can be freely adjusted by duty control, and pressurizes and supplies the fuel in the fuel tank to the injectors 11A to 11D. The valve timing actuator 14 is attached to the valve operating mechanism of the intake / exhaust valve, and can adjust the opening / closing valve timing of the intake / exhaust valve. The swirl actuator 15 drives a butterfly valve provided in the intake passage, and imbalances the amount of air flowing into the combustion chamber 102 in the intake valve to generate a swirling flow in a plane direction perpendicular to the cylinder axis. At the least, adjust the strength of the swirling flow according to the angle of the butterfly valve.

Further, the engine body 1 is provided with an exhaust gas recirculation device, and is provided with an EGR valve 16 for adjusting an exhaust gas recirculation amount (hereinafter, referred to as an EGR amount).

Cylinder block and cylinder head 101
The cooling system is configured such that cooling water is circulated by the power of a water pump, and includes a cooling water relief control valve 17 as cooling water temperature adjusting means. The cooling water relief control valve 17 is connected to the radiator 1
8 has a function similar to that of a conventional thermostat for switching whether to bypass or not, but has an electromagnetic solenoid and can be switched under the control of the ECU 2 described later.

The cooling water is supplied to the injectors 11A to 11A.
D is directly cooled. That is, in FIG. 2 described above, the lower portion of the mounting hole 103 for mounting the injector 11B has a larger diameter than the injector 11B, and an annular space 1001 is formed on the outer periphery of the injector 11B. The annular space 1001 is upper and lower 2
It is closed in a liquid-tight manner by seal members 104 and 105 at some places. The annular space 1001 communicates with a cooling water passage 1002 for cooling the cylinder head 101 formed inside the cylinder head 101, and cooling water is introduced.
This cooling water directly cools the injector tip 111 exposed to the combustion gas in the combustion chamber 102.

The engine body 1 is also provided with a basic structure of the internal combustion engine, for example, a throttle valve which opens according to the depression amount of an accelerator pedal.

The ECU 2 that performs fuel injection control, intake control, ignition control, and the like of the engine body 1 includes a CPU 211 and a RAM 21.
2, a general microcomputer 21 including a ROM 213, an input / output circuit 214, etc., and each of the injectors 11
The microcomputer 21 includes a driving circuit 22 for driving A to 11D and the like.
02, 303, 304, 305, 306, 307, 30
Operation parameters for controlling the injectors 11A to 11D and the like are set based on the operation state known from the detection signals of 8, 309, and the drive circuit 22 and the like send control signals to the injectors 11A to 11D and the like based on the operation parameters. Output. It should be noted that only the drive circuit 22 for operating the cooling water relief control valve 17 is shown.

As the sensors 301 to 309, an engine speed sensor 301 as a time interval detecting means for detecting an engine speed, a crank angle sensor 302 for detecting a crank angle, and a coolant temperature sensor 303 for detecting a coolant temperature. Accelerator opening sensor 304 for detecting the accelerator opening, intake air temperature sensor 3 for detecting the intake air temperature
05, an intake air amount sensor 306 for detecting an intake air amount,
An intake pipe pressure sensor 307 for detecting the intake pipe pressure, an exhaust O ₂ concentration sensor 308 for detecting the O ₂ concentration in the exhaust, and a fuel pressure sensor 309 for detecting the fuel pressure of the fuel supplied to the injectors 11A to 11D are provided.

In addition, the microcomputer 2
1, signals are input from general sensors for controlling the internal combustion engine.

The drive circuit 22 for the cooling water relief control valve 17 among the drive circuits for driving the injectors 11A to 11D will be described. Drive circuit 2
2 has a thermostat function in which the cooling water relief control valve is opened when the detected cooling water temperature exceeds a preset temperature threshold so that the cooling water flows through the radiator, and a control signal from the microcomputer 21 is provided. When input, the cooling water relief control valve 17 is opened and closed so that the detected cooling water temperature becomes a target temperature set in advance below the temperature threshold value. The control signal is issued when the detected engine speed is lower than a preset engine speed threshold value.

The control procedure in the microcomputer 21 will be described with reference to FIG. First, engine speed, accelerator opening, intake pipe pressure, cooling water temperature, injector temperature and the like are fetched (step S01), and based on these, operating parameters such as fuel injection amount, injection timing, ignition timing and the like are stored in the ROM 213. The setting is performed based on the operation parameter setting map (step S02).

Here, valve timing, swirl ratio,
The operation parameter setting map for the EGR amount, the fuel pressure, and the ignition timing is a map in which the engine speed and the coolant temperature are input.

As for the valve timing, for example, an exhaust valve is given a value on the advanced side as the engine speed is lower and the cooling water temperature is higher. This acts to shorten the time during which the combustion chamber holds the high-temperature combustion gas, and serves to lower the combustion chamber temperature.

The swirl ratio is given a larger value as the engine speed is higher and the cooling water temperature is lower. This acts in a direction in which the gas flow in the cylinder is strengthened to accelerate combustion, and thus acts in a direction in which the temperature in the combustion chamber increases.

The lower the engine speed, the greater the EGR amount.
A higher value is given as the cooling water temperature is higher. this is,
The ratio of the exhaust gas drawn into the combustion chamber increases, the specific heat ratio increases, and therefore, the temperature in the combustion chamber is reduced.

The higher the engine speed and the lower the injector temperature, the higher the fuel pressure. this is,
It acts in the direction of atomizing the fuel spray injected from the injector to accelerate combustion, and thus acts in the direction of increasing the temperature in the combustion chamber.

The ignition timing is set such that the lower the engine speed is,
The higher the cooling water temperature, the more the value on the retard side is given. This has the effect of shortening the time that the hot gas stays in the combustion chamber and thus suppressing the temperature inside the combustion chamber.

In step S03, a control signal is output to the drive circuit 22 and the like in accordance with the operation parameters set in step S02, and the circuit operates at a predetermined timing. As a result, an operation state corresponding to the operation parameters is established. That is, if the engine speed is low and the injector tip end temperature is high, each operating parameter is corrected in such a manner that combustion becomes slow or the combustion chamber temperature decreases.

As a result, the following operation is achieved. FIG.
The present inventors explain the findings obtained as a result of intensive experimental research on deposits adhering to the injection holes of the injector, and explain the time interval from the previous fuel injection to the current fuel injection (the following , Injection interval) and the rate of decrease in fuel flow rate. In the experiment, the injector for test was placed in the heating chamber, the same thermal environment as the operating engine was revealed in the heating chamber, and the flow rate of fuel injected from the injector was measured in this state. .

As can be seen from the figure, the longer the injection interval, the higher the flow rate decrease rate. This is considered because a part of the fuel remaining on the inner surface of the injection hole after the injection is vaporized, so that the longer the injection interval, the more the liquid fuel adheres to the inner surface of the injection hole. In other words, if the injection interval is short, the remaining fuel is easily washed away with the injected fuel by the fuel flow flowing through the injection hole at the time of the next fuel injection, whereas if the injection interval is long, the degree of sticking advances and the next Even if the fuel flow flows through the injection hole during fuel injection, part or all of the remaining fuel remains sticky, and the accumulation of deposits increases. As a result, the sectional area of the injection hole is reduced, and the injection flow rate is reduced.

According to the present invention, the engine speed is low,
Therefore, if the injection interval is long, the operation state shifts to a direction in which combustion becomes slow, and an increase in deposit accumulation is suppressed. On the other hand, if the engine speed is high and the injection interval is short,
The fuel is then washed away by the next injection before the fuel sticks. Thus, even if the deposited fuel is exposed to a high temperature, the deposition of the deposit does not increase. Therefore, if the engine speed is high, the operating state shifts in a direction in which combustion is rapid, so that efficient, that is, fuel-efficient operation can be realized.

Also, when the engine speed is low, and therefore the injection interval is long and it is necessary to watch for an increase in the deposit,
The drive circuit 22 controls the coolant relief control valve 17 so that the coolant temperature reaches the target temperature. Thus, rapid combustion with good fuel efficiency is performed with the injector tip 111 sufficiently cooled.

In the state where the cooling water temperature rises above the target temperature and the cooling capacity of the injector tip is insufficient, the parameters indicating the probability of the increase in the deposit (the engine speed that defines the injection interval, Depending on the cooling water temperature), measures are taken to avoid slow increase in deposits, such as a decrease in fuel pressure, in order to avoid an increase in deposits.

If the engine speed is high and the injection interval is short, the control for adjusting the cooling water temperature to the low target temperature is not performed, and it is possible to prevent the engine from being unnecessarily cooled due to a decrease in the cooling water temperature. .

As described above, according to the present invention, the injector tip temperature is prevented from rising excessively only when it is really necessary, instead of simply controlling the injector tip temperature to decrease. It can be compatible with high fuel efficiency.

The present invention can be applied to an internal combustion engine in which an injection mode in which fuel is injected twice in the compression stroke can be selected. In this case, by performing two injections, if the engine speed is the same, the injection interval is shorter than in the single injection mode. Therefore, for example, based on a correction made to increase the detected engine speed to the detected engine speed. The operation parameter setting map is read so that a value that causes relatively rapid combustion is given.

(Second Embodiment) This embodiment is different from the first embodiment in that a new sensor is provided as an operating state detecting means for detecting an operating state, and the operating parameters are set in a microcomputer under the condition of adding the new sensor. Is set. The basic configuration is the same as that of the first embodiment, and portions that operate substantially the same will be described with the same reference numerals as in the first embodiment.

In FIG. 5, which shows the mounting state of the injector 1B, the injector 11B is provided with an injector temperature sensor 310 as temperature detecting means. The injector temperature sensor 310 is formed of a thermocouple, and is provided along the outer surface of the injector 11B. Then, the hot junction is close to the opening position of the injection hole 112, and the temperature at the injection hole 112 position of the injector 11B can be substantially detected. Note that the injector temperature sensor 310 is provided in only one of the injectors 11A to 11D. The cylinder in which the injector temperature sensor 310 is provided is a cylinder in which the temperature of the combustion chamber tends to be high, and
It depends on the structure and layout of the internal combustion engine, individual differences, and the like.

The microcomputer 21 sets the operation parameters based on the detection signals of the sensors 301 to 309 as in the first embodiment. Then, the detected injector tip end temperature is compared with a preset temperature threshold value, and when the detected temperature exceeds the temperature threshold value, the valve timing, swirl ratio, EGR among the set operation parameters are set.
Corrections are made for quantity, fuel pressure, and ignition timing. The correction is performed by adding a correction value to the operation parameter or multiplying by a coefficient, so that the operation parameter shifts in a direction in which the combustion chamber temperature is suppressed, and the valve timing is set so that the exhaust valve is advanced. A correction value is provided so that the swirl ratio becomes a large value, the EGR amount increases, the fuel pressure decreases, and the ignition timing advances. The correction value is stored in the ROM in the same way as the operation parameter setting map.
213 is stored.

Then, the actuators 13 to 16 and the like operate according to the operation parameters.

According to this embodiment, even if the injector tip temperature tends to appear on the high-temperature side, for example, due to the aging of the engine, the difference in the properties of the fuel supplied, the load of the internal combustion engine, and the operating time, this is not the case. By detecting the section temperature, the operation parameter is reflected in the operation parameter and shifts to a direction in which the operation parameter becomes slow combustion.
Further, it is possible to suppress the deposit while realizing the fuel-efficient driving.

The temperature detecting means for detecting the temperature at the tip of the injector is not limited to a thermocouple, but may be a thermistor. Further, it is not always necessary to provide the thin film thermocouple or the like on a gasket provided in a close contact state between the injector and the cylinder head. In this case, the temperature detection position is slightly away from the injection hole formation position of the injector, but shows a high correlation between the detected temperature and the temperature of the injection hole formation position of the injector. This is equivalent to being provided on the front end face of the valve body of the injector.

As a method for indirectly detecting the injector injection hole position temperature as described above, a Wheatstone bridge circuit composed of four resistors including a solenoid is configured by regarding the solenoid of the injector as one resistor. , Two of the terminals connecting adjacent resistors
It is also possible to apply a voltage from one terminal to obtain a resistance value of the solenoid from a voltage between two opposite terminals and convert the resistance value to a temperature using a resistance / temperature conversion map stored in a ROM of the ECU.

Further, it is detected how much the exhaust O ₂ concentration changes from a reference value such as an initial value under the same idling condition, and the shortage of the injection flow rate is determined from the degree of progress of the leaning, and this is increased. Then, it may be determined that deposits are beginning to adhere, that is, the tendency of the injector tip to increase in temperature is progressing, and the operating parameters may be shifted in a direction in which combustion becomes slow. Again,
This is substantially equivalent to detecting the injector tip temperature and setting the operating parameters.

The injector temperature sensor is installed in a cylinder having the strongest tendency to increase the temperature, and the operating parameters of all the cylinders are set based on the detected temperature and a single operating parameter setting map. A setting map may be prepared for each cylinder. Further, the injector temperature sensors may be installed in all cylinders.

Whether or not the operation parameter is corrected is switched depending on whether the temperature at the tip of the injector is higher or lower than the temperature threshold, but the correction value is given in a plurality of steps or continuously according to the value of the temperature at the injector tip. Is also good. In this case, the operation parameter setting map may be a map in which three of the engine speed, the coolant temperature, and the injector tip end temperature are input.

In each of the above embodiments, the operation parameter setting map includes the valve timing, the swirl ratio,
It is not necessary that the EGR amount, the fuel pressure, and the ignition timing all change with the engine speed and the coolant temperature. The items whose contents change with the engine speed and the coolant temperature due to the required deposit suppression effect and the like. , One or more of the above items may be selected.

The valve timing, swirl ratio, EGR amount, fuel pressure, and ignition timing can change the temperature in the combustion chamber depending on the amount, advance or retard, independently of the values of other operating parameters. Although it is desirable, the operating parameters in which the temperature in the combustion chamber changes depending on the value are not only these.For example, the injection timing is such that, depending on the set timing, the propagating flame becomes the most intense near the injector tip, and in such a case, the combustion chamber becomes Since the temperature becomes high near the injector, the injection timing is set so as to avoid this.

Depending on the required deposit suppressing effect, it is not necessary to lower the cooling water temperature when the engine speed is low, and a conventional thermostat valve may control the cooling system.

Further, depending on the required deposit suppression effect, the operating parameter setting map does not need to input the cooling water temperature, and a value that simply lowers the combustion chamber temperature as the engine speed decreases. The operation parameter setting map is simplified by providing
The capacity burden of the OM can be reduced.

The present invention can also be applied to an internal combustion engine in which an injector is provided in an intake passage immediately upstream of an intake valve.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an internal combustion engine of the present invention.

FIG. 2 is a cross-sectional view of a part of the internal combustion engine showing an attached state of an injector.

FIG. 3 is a flowchart showing the control contents of a computer constituting the internal combustion engine.

FIG. 4 is a graph illustrating the operation of the internal combustion engine.

FIG. 5 is a cross-sectional view of a part of the internal combustion engine showing an attached state of an injector of another internal combustion engine of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Engine main body 11A, 11B, 11C, 11D Injector 111 Tip part 112 Injection hole 102 Combustion chamber 17 Cooling water relief control valve (Cooling water temperature adjusting means) 2 ECU 21 Microcomputer (Operating parameter setting means) 22 Drive circuit (Control means) ) 301 Engine speed sensor (operating state detecting means, time interval detecting means) 302, 304, 305, 306, 307, 308, 3
09 Sensors (operating state detecting means) 303 Cooling water temperature sensor (operating state detecting means, cooling water temperature detecting means) 310 Injector temperature sensor (operating state detecting means,
Injector temperature detection means)

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) F02D 13/02 F02D 13/02 H 3G084 45/00 345 45/00 345A 3G092 F02F 1/24 F02F 1/24 J 3G301 F02M 25/07 550 F02M 25/07 550R 550G 61/14 310 61/14 310Z F02P 5/15 F02P 5/15 B (72) Inventor: Kimitaka Saito 14th Iwatani, Shimowasumicho, Nishio, Aichi, Japan Inside the Automotive Parts Research Laboratory (72) Inventor Katsuyuki Mori 14 Iwatani, Shimowasumi-machi, Nishio City, Aichi Prefecture Inside the Japan Automotive Parts Research Institute (72) Inventor Shizuo Abe 1 Toyota-cho, Toyota-shi, Aichi Prefecture Toyota Motor Corporation In-house F term (reference) 3G022 AA10 DA02 EA01 FA06 GA05 GA06 GA07 GA08 GA09 GA11 3G023 AA15 AB01 AC05 AD06 AG03 3G024 AA04 BA29 CA05 DA01 FA00 3G062 BA04 BA05 BA08 BA09 FA03 GA01 GA02 GA04 GA06 GA08 GA15 GA17 GA26 3G066 AA02 AB02 BA32 CC31 DC09 DC13 3G084 BA13 BA14 BA15 BA17 BA20 FA10 FA02 DA10 3G092 AA01 AA06 AA10 AA11 AA17 DA02 DA08 EA03 FA15 FA24 HA01Z HA04Z HA05Z HB03Z HD05Z HE01Z HE08Z HF08Z 3G301 HA01 HA04 HA13 HA17 HA19 JA02 JA21 LA00 LA05 LA07 LB02 LB06 MA11 MA18 MA03 NC02 PE01Z03

Claims (7)

[Claims] An operating state detecting means for detecting an operating state of an engine main body which generates power by burning fuel spray injected from an injection hole formed at a tip end portion of an injector in a combustion chamber. And an operating parameter setting means for setting an operating parameter for controlling the engine body based on the detected operating state.In the internal combustion engine, as the operating state detecting means, the injection of the injector is performed based on the injection of the injector. A time interval detecting unit for detecting a time interval until the next injection, wherein the operation parameter setting unit sets the operation parameter to a value that decreases the temperature in the combustion chamber as the detected time interval is longer. An internal combustion engine characterized in that: 2. An internal combustion engine according to claim 1, wherein said time interval detecting means is constituted by engine rotation detecting means, and wherein said time interval is determined based on engine rotation. 3. The internal combustion engine according to claim 1, wherein said engine main body is provided with cooling water temperature detecting means for detecting a temperature of cooling water for cooling said engine main body. The internal combustion engine, wherein the operating parameter is set such that the higher the detected coolant temperature is, the lower the operating parameter is for decreasing the temperature in the combustion chamber. 4. The internal combustion engine according to claim 1, further comprising a temperature detecting means for detecting a temperature at a tip of the injector, wherein the operating parameter setting means is configured to detect a temperature of the detected tip of the injector. The internal combustion engine is set such that the operating parameter is set to a value that lowers the temperature in the combustion chamber as the pressure increases. 5. The internal combustion engine according to claim 4, wherein a plurality of injectors are provided so as to correspond to a plurality of cylinders on a one-to-one basis.
An internal combustion engine configured to substantially detect the temperature of the tip end of the injector, which has the highest tendency to increase in temperature. 6. The internal combustion engine according to claim 1, wherein said engine main body is provided with cooling water temperature adjusting means for adjusting a temperature of cooling water for cooling said engine main body. Control means for controlling the adjusting means, wherein the control means sets the cooling water temperature to a preset target temperature when the detected time interval is longer than a preset time threshold value. Internal combustion engine. 7. The in-cylinder engine according to claim 1, wherein a tip of the injector protrudes into the combustion chamber, and the engine body directly injects fuel from the injection hole into the combustion chamber. Type internal combustion engine.