JP3313242B2 - Fuel injection valve control system for in-cylinder injection internal combustion engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel injection valve control system for a direct injection type internal combustion engine in which a fuel pressure is switched between a low pressure and a high pressure in accordance with, for example, an operation state, and more particularly, irrespective of a fuel injection pulse width. At low pressure, fuel injection during the compression stroke is prohibited.At high pressure, fuel injection during the explosion stroke is prohibited.At the time of ignition, fuel injection is prohibited. The present invention relates to a fuel injection valve control device for an in-cylinder injection internal combustion engine, which prevents deterioration and improves reliability.

[0002]

2. Description of the Related Art A direct injection type spark ignition internal combustion engine provided with a fuel injection valve for directly injecting fuel into a cylinder of an engine has been well known. This type of internal combustion engine performs stratified combustion by injecting fuel in the latter half of the compression stroke at low load, and performs weak stratified combustion by injecting fuel in the intake stroke and the latter half of the compression stroke at medium and high load. ing.

FIG. 14 shows, for example, Japanese Patent Application Laid-Open No. 2-169834.
FIG. 1 is a configuration diagram showing a conventional fuel injection valve control device for a direct injection internal combustion engine described in Japanese Patent Application Laid-Open Publication No. H10-209,878. In the figure, reference numeral 1 denotes an engine serving as a main body of an internal combustion engine; 2, a surge tank for supplying air to the engine 1; 3, an air cleaner for purifying sucked air; 4, a communication between the air cleaner 3 and the surge tank 2; An intake pipe 5, an electrostrictive fuel injection valve 5 for directly injecting fuel into each cylinder of the engine 1, and a spark plug 6 for generating a spark for burning an air-fuel mixture in each cylinder.

[0004] 7 is a high-pressure fuel pump for supplying high-pressure fuel to the fuel injection valve 5, 8 a is a high-pressure pipe through which high-pressure fuel is drawn from the high-pressure fuel pump 7, and 8 b stores high-pressure fuel passed through the high-pressure pipe 8 a. A reservoir tank 8c is a branch pipe for communicating the reservoir tank 8b with each fuel injection valve 5,
d is a piezoelectric element cooling introduction pipe to which fuel for cooling the piezoelectric element of each fuel injection valve 5 is supplied, and 8e is a piezoelectric element cooling return pipe that collects cooling fuel flowing through the piezoelectric element cooling introduction pipe 8d. A pipe 9 is a fuel tank for supplying a high-pressure fuel and collecting a cooling fuel, and a low-pressure fuel pump 10 is for supplying fuel from the fuel tank 9 to the high-pressure fuel pump 7.

A crank angle sensor 14 outputs a crank angle signal CA indicating the crank angle of the engine 1. For example, the crank angle sensor 14 outputs a crank angle signal CA based on the rotation angle of a distributor (not shown) for supplying a high voltage to the ignition plug 6. Generates an output pulse proportional to the rotation speed Ne.

An accelerator opening sensor 14a detects an accelerator opening α, and generates a voltage signal corresponding to the amount of depression of an accelerator pedal (not shown). 14b is a pressure sensor for detecting the pressure Pr in the reservoir tank 8b. Various other sensors for detecting the operating state of the engine 1 are not shown.

Reference numeral 15 denotes an electronic control unit (ECU) which constitutes a fuel injection control device using a microcomputer. The interface 16 receives various sensor signals and outputs control signals to various actuators.
And a CPU 17 having various arithmetic processing functions and the like;
And a memory 18 associated with U17. The interface 16 and the memory 18 are connected to a CPU via a bidirectional bus.
17 are connected.

The interface 16 includes a pressure sensor 14
AD converter 16a for converting the pressure Pr from b into a digital signal, and A for converting the accelerator opening α into a digital signal
A D converter 16b, an input port 16c for taking in a crank angle signal CA together with various sensor signals via the AD converters 16a and 16c, an output port 16d for outputting control signals for various actuators, and an output port 1
A drive circuit 16e for supplying a control signal from the fuel injection valve 5 to the ignition plug 6; a drive circuit 16f for supplying a control signal from the output port 16d to each spark plug 6;
and a drive circuit 16g for supplying the control signal from the high pressure fuel pump 7 to the high pressure fuel pump 7.

The memory 18 has a ROM 18a in which an arithmetic program for operating the CPU 17 and the like are stored.
And a RAM 18b for storing arithmetic processing data and the like.

The ECU 15 switches the fuel pressure supplied to the fuel injection valve 5 to a low pressure or a high pressure in accordance with the operating state of the engine 1 and a fuel pressure switching means in accordance with the operating state of the engine 1 and the crank angle signal CA. Injection timing control means for controlling the injection timing of the fuel injection valve 5,
It is assumed that the engine 1 includes an ignition timing control means for controlling the timing of energizing the ignition plug 6 according to the operating state of the engine 1 and the crank angle signal CA.

FIG. 15 is a longitudinal sectional view showing the structure of one cylinder of the engine 1. Reference numeral 60 denotes a cylinder block, 61 denotes a cylinder head, 62 denotes a piston driven in the cylinder 6, and 63 denotes a top surface of the piston 62. A substantially cylindrical recess formed in
Reference numeral 4 denotes a combustion chamber formed on the top surface of the piston 62 and the inner wall surface of the cylinder head 61, and K denotes an uneven distribution region of the fuel injected from the fuel injection valve 5 into the combustion chamber 64.

[0015] As shown in FIG. 15, the ignition plug 6 is disposed in the combustion chamber 64 and is attached to a substantially central portion of the cylinder head 61. The fuel injection valve 5 is formed of a swirl-type injection valve disposed at the top of the combustion chamber 64, and directs the spray-like fuel having a large divergence angle and a low penetration force obliquely downward and toward the ignition plug 6. To be injected. Further, the fuel injection direction and the fuel injection timing are determined so that the injected fuel is directed to the concave portion 63 formed at the top of the piston 62.

Although not shown, an intake port and an exhaust port are formed in the cylinder head 61, and an intake valve and an exhaust valve are disposed at openings of these ports to the combustion chamber 64, respectively. . Hereinafter, the operations of the conventional compression stroke injection and intake stroke injection will be described with reference to FIG.

FIG. 16 is an explanatory diagram showing each control pattern of the compression stroke injection and the intake stroke injection. The horizontal axis indicates the load corresponding to the fuel injection amount, and the vertical axis indicates the fuel injection amount Q. FIG.
In the range from the low load to the fuel injection amount Qs near the medium load, fuel is injected only in the compression stroke. The compression stroke fuel injection amount at this time is the fuel injection amount Qs near the medium load.
Is gradually increased to

Thus, when the fuel injection amount Qs from low load to near medium load is reached, the compression stroke fuel injection amount sharply decreases to QD, and at the same time, the intake stroke fuel injection amount sharply increases from 0 to Qp. At this time, the fuel injection amount Qs near the medium load is Q
The sum of D and Qp is expressed as follows.

Qs = QD + Qp

Here, QD is a minimum compression stroke fuel injection amount capable of forming an air-fuel mixture ignitable by the ignition plug 6, and Qp is a value when the fuel injected in the intake stroke diffuses into the combustion chamber 64. This is the minimum intake stroke fuel injection amount through which the ignition flame from the spark plug 6 can propagate.

In the load region where the fuel injection amount is larger than Qs, as shown in FIG. 15, the compression stroke injection is performed in the latter half of the compression stroke, and the fuel injection valve 5 and the spark plug 6 and the concave portion on the top surface of the piston 62 Fuel is injected in the direction of 63. At this time, the injected fuel has a low penetration force, and the pressure in the combustion chamber 64 is high and the air flow is weak, so the injected fuel is unevenly distributed in the region K near the ignition plug 6.

At this time, the fuel distribution in the region K is non-uniform and changes from a rich mixture layer to an air layer.
In the region K, there is a combustible air-fuel mixture layer near the stoichiometric air-fuel ratio where combustion is most likely to occur. Therefore, the combustible air-fuel mixture layer near the ignition plug 6 is easily ignited, and the ignition flame propagates to the entire non-uniform air-fuel mixture layer, completing the combustion.

As described above, in the low-load region lower than the medium load, the fuel is injected in the latter half of the compression stroke and the ignition plug 6
By forming a combustible mixture layer in the vicinity of, good ignition and combustion can be obtained after a while.

On the other hand, in the load region near the middle load where the fuel injection amount Qs is higher, the intake stroke injection is performed at the beginning of the intake stroke, and a part of the injected fuel at this time floats in the combustion chamber 64, The injected fuel collides with the recess 63. These injected fuels are diffused by the turbulence in the combustion chamber 64 caused by the intake air flowing from the intake port, and a premixed gas is formed during the compression stroke. The air-fuel ratio of the premixed gas is such that the ignition flame can propagate.

Subsequently, after the compression stroke injection is performed in the same manner as described above, when ignition occurs, combustion proceeds around the region K of the heterogeneous mixture. Then, the flame is sequentially propagated from the periphery of the combustion gas whose volume has expanded in the combustion process to the premixed gas, and the combustion is completed.

However, in the above-described conventional apparatus, fuel injection is performed during the compression stroke. Therefore, in an operating state in which the engine speed Ne suddenly increases during acceleration or the like, a part of the fuel injection pulse is applied to the explosion stroke. Or after the ignition by the ignition plug 6 is completed. For this reason, sufficient combustion cannot be obtained, or the emission of unburned gas causes deterioration of exhaust gas.

Further, conventionally, there has been proposed a device for switching the fuel pressure which can be supplied to the fuel injection valve 5 between a low pressure and a high pressure in accordance with an operation state without using a fuel pressure sensor.
For example, under normal conditions (almost all operating conditions)
Although the fuel pressure is set to a high pressure, the fuel pressure does not immediately become high at the time of starting the engine or for a while after the engine is started, so the fuel pressure is set to a low pressure during this time.

In this case, the fuel control device cannot control the fuel amount unless the fuel pressure is known. Therefore, during a transitional period until the fuel pressure reaches a high pressure, for example, the high pressure valve is closed and set to a low pressure, and after a certain period of time, when the fuel pressure reaches a sufficiently high pressure, the high pressure valve is turned on. Open to switch fuel pressure to high pressure.

However, when a fuel pressure sensor is provided, it is not necessary to switch the fuel pressure since the fuel pressure is known and the fuel amount can be controlled. In the internal combustion engine that switches the fuel pressure as described above, when the intake stroke injection is performed at a low pressure, the engine speed Ne sharply increases due to acceleration, and when a part of the fuel injection pulse is applied to the compression stroke, the fuel pressure increases. Since the pressure of the fuel discharge port is higher than that of the fuel injection port, the fuel injection valve 5 may be damaged.

[0027]

As described above, the conventional fuel injection valve control system for a direct injection internal combustion engine operates in such a manner that when the fuel injection is performed during the compression stroke, the engine speed Ne sharply increases. In this case, since a part of the fuel injection pulse may be applied after the explosion process or the end of the ignition, there is a problem that sufficient combustion cannot be obtained or exhaust gas is deteriorated due to discharge of unburned gas.

In particular, in an internal combustion engine in which the fuel pressure is switched between low pressure and high pressure in accordance with the operating state, when performing the intake stroke injection at a low pressure, the engine speed Ne sharply increases and a part of the fuel injection pulse is increased. However, there is a problem that the fuel injection valve 5 may be damaged because the compression stroke may take place.

[0029] Claims 1, 2, and 4 of the present invention.
The present invention has been made to solve the above-described problems, and prohibits fuel injection during the compression stroke at low pressure regardless of the fuel injection pulse width. It is an object of the present invention to provide a fuel injection valve control apparatus for a direct injection internal combustion engine, which has improved reliability by preventing deterioration of exhaust gas.

Further, in the first, third and sixth aspects of the present invention, regardless of the fuel injection pulse width, the fuel injection during the explosion stroke is prohibited at the time of high pressure, and the fuel injection valve is damaged or the exhaust gas is exhausted. It is an object of the present invention to provide a fuel injection valve control device for a direct injection internal combustion engine, which has improved reliability by preventing deterioration of gas.

[0031] Further, claims 7 to 10 of the present invention.
The fuel injection valve of a direct injection internal combustion engine with improved reliability by prohibiting fuel injection during ignition and preventing damage to the fuel injection valve and deterioration of exhaust gas regardless of the fuel injection pulse width The aim is to obtain a control device.

[0032]

According to a first aspect of the present invention, there is provided a fuel injection valve control system for a direct injection internal combustion engine, comprising: a fuel injection valve for directly injecting fuel into each cylinder of the internal combustion engine; A spark plug for igniting fuel in each cylinder, fuel pressure switching means for switching the fuel pressure supplied to the fuel injection valve to low pressure or high pressure in accordance with the operation state of the internal combustion engine, and a crank angle of the internal combustion engine Crank angle detection means for detecting, injection timing control means for controlling fuel injection timing according to the operating state of the internal combustion engine and the crank angle, and power supply timing to the ignition plug according to the operating state of the internal combustion engine and the crank angle. In a fuel injection valve control device for a direct injection internal combustion engine having an ignition timing control means for controlling, a pressure based on identification of a piston top dead center of a specific cylinder is determined.
A stroke identification means for identifying a cylinder in a contraction stroke or an explosion stroke is provided, and the injection timing control means responds to a switching state of the fuel pressure switching means and a stroke identification result to determine a fuel
Cylinder or fuel pressure during compression stroke when pressure is low
When the power is high, the fuel injection of the cylinder during the explosion stroke is prohibited.

According to a second aspect of the present invention, there is provided a fuel injection valve control apparatus for a direct injection internal combustion engine, wherein the injection timing control means includes a reference crank angle based on an operating state of the internal combustion engine. An injection start time calculating means for calculating a fuel injection start time from a position, an injection end time calculating means for calculating a fuel injection end time from a reference position of the crank angle, and a fuel injection after a first predetermined time has elapsed. An injection start timer for opening the valve, an injection end timer for closing the fuel injection valve after a lapse of a second predetermined time, an injection start time setting means for setting the injection start time to the injection start timer, and an injection end time And an end-of-injection time setting means for setting an injection end timer to the injection end timer, wherein the stroke identification means identifies a cylinder in a compression stroke based on the crank angle and the top dead center of the specific cylinder, Time setting means, with respect to the cylinder in which the fuel pressure is and during the fuel injection during the compression stroke in the case of low pressure, closes the fuel injection valve is to stop the supply of fuel to the start of the next fuel injection.

According to a third aspect of the present invention, there is provided a fuel injection valve control apparatus for a direct injection internal combustion engine, wherein the injection timing control means includes a reference crank angle based on an operation state of the internal combustion engine. An injection start time calculating means for calculating a fuel injection start time from a position, an injection end time calculating means for calculating a fuel injection end time from a reference position of the crank angle, and a fuel injection after a first predetermined time has elapsed. An injection start timer for opening the valve, an injection end timer for closing the fuel injection valve after a lapse of a second predetermined time, an injection start time setting means for setting the injection start time to the injection start timer, and an injection end time And an end-of-injection time setting means for setting an injection end timer to the injection end timer, wherein the stroke identification means identifies a cylinder in an explosion stroke based on the crank angle and the top dead center of the specific cylinder, Time setting means, the fuel pressure to the cylinder in the and during the fuel injection in the explosion stroke when the high pressure, closes the fuel injection valve is to stop the supply of fuel to the start of the next fuel injection.

According to a fourth aspect of the present invention, in the fuel injection valve control device for a direct injection internal combustion engine, the stroke discriminating means according to the second aspect further comprises: When the fuel pressure is high, the injection end time setting means closes the fuel injection valve for the cylinder that is in the explosion stroke and is injecting the fuel while the fuel pressure is high. This is to stop the supply.

According to a fifth aspect of the present invention, there is provided a fuel injection valve control apparatus for a direct injection type internal combustion engine, wherein the injection start time setting means is arranged so that when the fuel pressure is low, In the compression stroke, the fuel injection start time is set, and the setting of the injection start time is canceled for the cylinder before the fuel injection, and the supply of the fuel is stopped until the next fuel injection starts.

According to a sixth aspect of the present invention, there is provided a fuel injection valve control apparatus for a direct injection internal combustion engine, wherein the injection start time setting means is arranged so that when the fuel pressure is high, The fuel injection start time is set during the explosion stroke and the setting of the injection start time is released to the cylinder before the fuel injection, and the supply of the fuel is stopped until the next fuel injection starts.

According to a seventh aspect of the present invention, there is provided a fuel injection valve control apparatus for a direct injection internal combustion engine, wherein the injection end time setting means includes an ignition timing control. Spark plug turned off by the means
Is closed and the fuel injection valve is closed and the supply of fuel is stopped until the next fuel injection is started.

According to an eighth aspect of the present invention, there is provided a fuel injection valve control apparatus for a cylinder injection type internal combustion engine, wherein the injection start time setting means includes an ignition timing control unit. Spark plug turned off by the means
Is mounted, the fuel injection start time is set, and the setting of the injection start time is released to the cylinder before the fuel injection, and the supply of fuel is stopped until the next fuel injection starts.

According to a ninth aspect of the present invention, there is provided a fuel injection valve control apparatus for a direct injection internal combustion engine, comprising: a fuel injection valve for directly injecting fuel into each cylinder of the internal combustion engine; Spark plug for igniting fuel, crank angle detecting means for detecting a crank angle of the internal combustion engine, injection timing control means for controlling fuel injection timing according to the operating state of the internal combustion engine and the crank angle, and the internal combustion engine the fuel injection valve control apparatus for a cylinder injection internal combustion engine with an ignition timing control means for controlling the energization timing to the spark plug according to the operating condition and the crank angle, the identification of the piston top dead center of a particular cylinder During the compression stroke or explosion based
A stroke identification means for identifying a cylinder in the stroke is provided, and the injection timing control means terminates energization of the ignition plug by the ignition timing control means based on the stroke identification result;
The fuel injection valve is closed and the supply of fuel is stopped until the next fuel injection is started for the cylinder that is performing fuel injection during the compression stroke or the explosion stroke .

According to a tenth aspect of the present invention, there is provided a fuel injection valve control device for a direct injection internal combustion engine, comprising: a fuel injection valve for directly injecting fuel into each cylinder of the internal combustion engine; Spark plug for igniting fuel, crank angle detecting means for detecting a crank angle of the internal combustion engine, injection timing control means for controlling fuel injection timing according to the operating state of the internal combustion engine and the crank angle, and the internal combustion engine the fuel injection valve control apparatus for a cylinder injection internal combustion engine with an ignition timing control means for controlling the energization timing to the spark plug according to the operating condition and the crank angle, the identification of the piston top dead center of a particular cylinder During the compression stroke or explosion
A stroke identification means for identifying a cylinder during the issuance stroke is provided, and the injection timing control means terminates the energization of the spark plug by the ignition timing control means based on the stroke identification result. Time is set and during compression stroke or explosion
At the start of injection for the cylinder before the fuel injection during the issuance process
The setting of the time is canceled and the supply of fuel is stopped until the next fuel injection starts.

[0042]

According to the first aspect of the present invention, in response to the stroke identification result, fuel injection into a cylinder which may cause trouble due to fuel supply is prohibited.

According to a second aspect of the present invention, the fuel injection valve is closed for the cylinder determined to be in the compression stroke when the fuel pressure is low, and the supply of fuel is stopped until the next fuel injection starts. I do. This prohibits fuel injection during the compression stroke when the fuel pressure is low even when the engine speed is rapidly increasing.

According to a third aspect of the present invention, the fuel injection valve is closed for a cylinder determined to be in an explosion stroke when the fuel pressure is high, and the supply of fuel is stopped until the next fuel injection starts. I do. This prohibits fuel injection during the explosion stroke when the fuel pressure is high even when the engine speed is rapidly increasing.

According to a fourth aspect of the present invention, the fuel injection valve is closed and the supply of fuel is stopped until the start of the next fuel injection for the cylinder determined to be in the compression stroke when the fuel pressure is low. At the same time, the fuel injection valve is closed for the cylinder determined to be in the explosion stroke when the fuel pressure is high, and the supply of fuel is stopped until the next fuel injection starts. This prohibits fuel injection during the compression stroke when the fuel pressure is low and fuel injection during the explosion stroke when the fuel pressure is high even when the engine speed is rapidly increasing.

According to the fifth aspect of the present invention, the setting of the injection start time is performed for a cylinder in which the fuel injection is started and the fuel injection is not started during the compression stroke when the fuel pressure is low. And the supply of fuel is stopped until the start of the next fuel injection. This prohibits fuel injection during the compression stroke when the fuel pressure is low even when the engine speed is rapidly increasing.

According to a sixth aspect of the present invention, an injection start time is set for a cylinder in which an injection start time is set and fuel injection is not started during an explosion stroke when the fuel pressure is high. And the supply of fuel is stopped until the start of the next fuel injection. This prohibits fuel injection during the explosion stroke when the fuel pressure is high even when the engine speed is rapidly increasing.

[0048] Further, claims 7 and 9 of the present invention.
In the above, if the cylinder to which the equal spark plug is mounted is performing fuel injection when the energization of the spark plug is completed, the fuel injection valve of the equal cylinder is closed and the fuel is supplied until the next fuel injection starts. Stop. This prevents the emission of unburned gas.

[0049] In addition, claims 8 and 1 of the present invention.
0, the fuel injection start time is set for the cylinder to which the same spark plug is mounted when the current supply to the spark plug is completed and before the fuel injection, the setting of the injection start time is released, and the next The fuel supply is stopped until the start of the fuel injection. This prevents the emission of unburned gas.

[0050]

【Example】

Embodiment 1 FIG. Embodiment 1 Embodiment 1 of the present invention will be described below with reference to the drawings. FIG.
1 is a block diagram showing a first embodiment of the present invention, wherein 1 to 10 and 14 to 18 are the same as those described above. It should be noted that here, a configuration not directly related to the present invention (for example, FIG.
The illustration of the reservoir tank 8b in 4) is omitted.
As a fuel supply path, only the high-pressure conduit 8 is typically shown.

In this case, the crank angle signal CA includes a cylinder identification signal, and the ECU 15 determines the piston top dead center (TDC) of the specific cylinder (first cylinder) based on the crank angle signal CA.
Process identification means for identifying Also, EC
U15 the injection timing control means of the internal, in response to the switching state and stroke identification result of the fuel pressure switching means, the fuel pressure
Cylinder or fuel pressure during compression stroke at low pressure
When the pressure is high, the fuel injection of the cylinder during the explosion stroke is prohibited.

The injection timing control means in the ECU 15 calculates the fuel injection start time from the reference position of the crank angle in accordance with the operating state of the engine 1, and the injection timing control means calculates the start time of the fuel from the reference position of the crank angle. A fuel injection end time calculating means for calculating the fuel injection end time, an injection start timer for opening the fuel injection valve after the first predetermined time has elapsed, and a fuel injection valve for closing the fuel injection valve after the second predetermined time has elapsed. , An injection start time setting means for setting the injection start time to the injection start timer, and an injection end time setting means for setting the injection end time to the injection end timer.

The stroke identification means in the ECU 15 identifies the cylinder in the compression stroke on the basis of the crank angle and the top dead center of the specific cylinder, and the injection end time setting means sets the compression time when the fuel pressure is low. The fuel injection valve 5 is closed and the supply of fuel is stopped until the next fuel injection is started for the cylinders during the stroke and during the fuel injection.

Further, the stroke identification means in the ECU 15
Based on the crank angle and the top dead center of the specific cylinder, the cylinder in the explosion stroke is identified, and the injection end time setting means sets the fuel in the cylinder in the explosion stroke and during the fuel injection when the fuel pressure is high. The injection valve is closed and the supply of fuel is stopped until the start of the next fuel injection.

Reference numeral 11 denotes a fuel pressure switching valve attached to the reserve side of the high-pressure conduit 8 and is controlled by the ECU 15. Reference numeral 12 denotes a low-pressure regulator provided downstream of the high-pressure conduit 8 so as to be in series with the fuel pressure switching valve 11, and reference numeral 13 denotes a high-pressure regulator provided in parallel with the fuel pressure switching valve 11.

Next, the operation of the first embodiment of the present invention shown in FIG. 1 will be described with reference to the flowcharts of FIGS. 2 to 7 are stored in the memory 18 in the ECU 15 in advance.

During the treatment of the main routine (step S200) of FIG. 2, the CPU 17 in the ECU 15 performs the prescribed crank angle routine (step S300) of FIGS. The injection start interrupt routine of FIG. 6 (step S
400), and every time the energization signal of the ignition plug 5 is cut off, the ignition energization signal off interrupt routine (step S500) of FIG. 7 is executed.

First, the main routine of FIG. 2 (step S
At 200), the operation state, that is, the operation mode of the engine 1 is calculated based on signals from various sensors (not shown) attached to the engine 1 (step S20).
1). Subsequently, injection end timing data from the reference position of the crank angle is calculated according to the operation mode (step S2).
02) Further, the fuel pressure mode to be supplied to the fuel injection valve 5 is set to a low pressure or a high pressure according to the operation mode (step S203).

Next, it is determined whether or not the fuel pressure mode set in step S203 is a low pressure (step S20).
4) If the pressure is low (that is, YES), the fuel pressure switching valve 11 is opened (step S205), the fuel pressure in the high pressure pipe 8 is limited by the low pressure regulator 12, and the processing of the main routine (step S200) Is completed (step S207).

If it is determined in step S204 that the fuel pressure is high (that is, NO), the fuel pressure switching valve 11 is closed (step S206), and the fuel pressure in the high pressure conduit 8 is limited by the high pressure regulator 13. The processing of the main routine (step S200) is ended (step S207). The above processing steps correspond to a normal fuel pressure switching operation.

Next, a predetermined crank angle routine (step S300) according to the first embodiment of the present invention will be described with reference to FIGS. First, an intake air amount is calculated based on a sensor signal from an air flow sensor (not shown) (step S301), and a fuel injection pulse width T2 is calculated based on the calculated intake air amount (step S301).
302).

Subsequently, step S2 in the main routine
The injection end time data obtained in step 02 is converted from the angle data of the crank angle from the reference position into time data to obtain an injection end time Te (step S303), and based on the cylinder identification signal included in the crank angle signal CA. The specific cylinder and other cylinders are identified (step S304).

Next, based on the cylinder identification result in step S304, it is determined whether each cylinder is in the compression stroke and whether it is in the explosion stroke. If the cylinder is in the compression stroke, it indicates that the cylinder is in the compression stroke. A compression stroke flag is set, and if it is an explosion stroke, an explosion stroke flag indicating that an explosion stroke is being performed is set (step S305).

Here, the case of four cylinders is shown, and in step S305, each flag is set for #n cylinders (n = 1 to 4). The compression stroke flag is cleared when it is determined that the stroke is not a compression stroke, and the explosion stroke flag is cleared when it is determined that the stroke is not an explosion stroke.

Subsequently, a cylinder at which fuel injection is started is set based on the result of cylinder identification in step S304 (step S306). Further, the fuel injection pulse width determined in step S302 and the injection end determined in step S303. The fuel injection start time T1 is calculated based on the time Te (step S307). That is, the fuel injection pulse width T
2 and the injection end time Te, the fuel injection start time T1 is expressed as follows.

T1 = Te−T2

Next, step S20 in the main routine
It is determined whether the fuel pressure is low based on the setting result of step 3 (step S308).
If S), it is determined whether or not the compression stroke flag of the cylinder #n to be fuel-injected is set by referring to the flag set in step S305 (step S30).
9). On the other hand, if it is determined in step S308 that the fuel pressure is high (that is, NO), it is determined whether or not the explosion stroke flag of the cylinder to be injected is set (step S310).

In step S309, the compression stroke flag of the target cylinder is set (that is, YE).
If it is determined as S), it is determined whether or not the injection start flag of the #n cylinder is set (step S311), and if the injection start flag is already set (that is, YE).
If determined as S), it is determined whether or not the #n cylinder is performing fuel injection (step S312).

If it is determined in step S312 that fuel injection is not being performed (that is, NO), 0 is set in the injection start timer of cylinder #n, and fuel injection is started immediately (step S313).

Subsequently, it is determined whether or not the #n cylinder is performing fuel injection (step S314). If the fuel is being injected (that is, YES), 0 is set to the injection end timer of the #n cylinder.
Is set and fuel injection is immediately stopped (step S31).
5) Also, in step S315, the injection start flag of the #n cylinder is cleared (step S316).

Next, the #m cylinder (m = 1 to 4) at which fuel injection is started this time set in step S306 is read (step S317), and the fuel injection calculated in step S307 is performed on the #m cylinder. The start time data is set in the injection start timer (step S318).

At this time, the injection start timer is set in the CPU 17 in advance so that the fuel injection valve 5 is opened (ie, the fuel injection is started) after the time T1 corresponding to the fuel injection start time data has elapsed. .

Next, an injection start flag is set for the #m cylinder (step S319), and the predetermined crank angle routine (step S300) ends (step S32).
0).

At step S309, the compression stroke flag for cylinder #n is cleared (ie, NO).
If it is determined that, it skips steps S311 to S316 and proceeds to step S317.

In step S310, an explosion stroke flag for cylinder #n is set (ie, YES).
If it is determined that the explosion stroke flag for the #n cylinder is clear (that is, NO), the process proceeds to step S317.

In step S311, the injection start flag for the #n cylinder is cleared (ie, NO).
Is determined, or in step S312, #
When it is determined that fuel injection is being performed on the n cylinders (that is, YES), the process proceeds to step S314.

Further, in step S314, #n
If it is determined that the cylinder is not performing fuel injection (that is, NO), the process skips steps S315 and S316 and proceeds to step S317.

Next, the injection start interrupt routine (step S400) executed at each injection start timing will be described with reference to FIG. In this routine, an injection start timer is set, and interrupt processing is executed at a timing when the set time has elapsed.

First, the k-th # at which the injection start interrupt was performed
The k cylinders (k = 1 to 4) are identified (step S40).
1) The injection end time corresponding to the fuel injection pulse width T2 calculated in step S302 is set in the injection end timer for the #k cylinder (step S402). At this time, the injection end timer determines in advance C so that the fuel injection valve 5 of the #k cylinder is closed (that is, the fuel injection is stopped) after the time corresponding to the set data has elapsed.
It is set to PU17.

Subsequently, the injection start flag for the #k cylinder is cleared, and the injection start interrupt routine (step S40)
0) is ended (step S404).

Next, the ignition energizing signal off interrupt routine (step S500) will be described with reference to FIG. This routine is interrupted every time the ignition energizing signal to the ignition plug 6 is turned off and ignition is performed. In FIG. 7, S501 to S509 are the same steps as S308 to S316 in FIG.

In this case, each of steps S501 to S509
, The same processing as the above-described steps S308 to S316 is performed, but in step S502, the compression stroke flag for the #n cylinder is cleared (that is, NO).
When the determination is made, the routine of FIG. 7 ends (step S510).

In step S503, the explosion stroke flag for cylinder #n is cleared (ie, NO).
When the determination is made, and when it is determined in step S507 that the #n cylinder is not performing the fuel injection (that is, NO), the routine of FIG. 7 ends. Also,
After the injection start flag for the #n cylinder is cleared in step S509, the routine of FIG. 7 ends.

Next, FIG. 8 (corresponding to claim 2) and FIG.
The control operation according to the first embodiment of the present invention will be described in further detail with reference to the timing chart of FIG. 8 shows the control operation of the fuel injection valve 5 of the first cylinder (# 1 cylinder) when the fuel pressure is in the low pressure mode, and FIG. 9 shows the control operation of the fuel injection valve 5 of the first cylinder in the high pressure mode. .

First, the operation of controlling the fuel injection valve when the fuel pressure is in the low pressure mode will be described with reference to FIG.
FIG. 8 shows the operation of the fuel injection valve 5 in association with the crank angle signal CA, the stroke of the first cylinder, the fuel pressure mode, the compression stroke flag of the first cylinder, and the injection start flag.

In FIG. 8, tA is the crank angle signal CA
, T1 is a first predetermined time (injection start time) set in the injection start timer,
tB is an injection start time, T2 is a second predetermined time (injection end time corresponding to the fuel injection pulse width) set in the injection end timer, tC is an actual injection end time controlled based on the compression stroke flag, Te is the injection end time set with reference to the timing time tA, tD (broken line position) is the set injection end time, and tAa is the timing time at which the next injection start is set. Hereinafter, the timing time is simply referred to as time.

First, at time tA, an injection start time T1 is set in an injection start timer for the first cylinder, and at the same time, an injection start flag for the first cylinder is set. The injection start time T1 is such that the fuel injection valve 5 is opened at time tB.

Next, at time tB, the fuel injection valve 5 of the first cylinder is opened, and at the same time, the injection end time T2 is set in the injection end timer for the first cylinder, and the injection start flag for the first cylinder is cleared. I do. Injection end time T2
Is configured to close the fuel injection valve 5 at time tD.

Normally, the injection end time in the low pressure mode is set before the time tC (solid line) at which the intake stroke ends, and the fuel injection valve 5 is not opened until the compression stroke is reached. When Ne rises sharply, the injection end time can be shifted to tD (broken line).

However, as shown in FIG.
Even if it is set to D, if the fuel injection valve 5 is open at the time tC when the compression stroke flag is set, the first
The injection end timer of the cylinder is set to "0" and the fuel injection valve 5 is immediately closed. Therefore, in the low pressure mode, fuel is not injected into the cylinder during the compression stroke, and the exhaust gas does not deteriorate.

The next start of injection for the first cylinder is set at time tAa using time tAa as a reference position. Here, the first cylinder has been described as an injection control target, but the same applies to other cylinders.

Next, the operation of controlling the fuel injection valve when the fuel pressure is in the high pressure mode will be described with reference to FIG.
FIG. 9 shows the operation of the fuel injection valve 5 in association with the crank angle signal CA, the stroke of the first cylinder, the fuel pressure mode, the explosion stroke flag of the first cylinder, and the injection start flag.
In FIG. 9, tA to tD, T1, T2, Te and t
Aa is the same as described above.

First, at time tA, an injection start time T1 for opening the fuel injection valve 5 of the first cylinder at time tB is set, and at the same time, an injection start flag is set. Further, at time tB, the fuel injection valve 5 is opened, an injection end time T2 for closing the fuel injection valve 5 of the first cylinder at time tD is set, and at the same time, the injection start flag is cleared.

Normally, the injection end time in the high pressure mode is set before the time tC (solid line) at which the compression stroke ends, and the fuel injection valve 5 is not opened until it reaches the explosion stroke. When Ne rises sharply, the injection end time can be shifted to tD (broken line).

However, as shown in FIG.
Even if it is set to D, if the fuel injection valve 5 is open at the time tC when the explosion stroke flag is set, the first
The injection end timer of the cylinder is set to "0" and the fuel injection valve 5 is immediately closed. Therefore, in the high pressure mode, fuel is not injected into the cylinder during the explosion stroke, and the exhaust gas does not deteriorate.

Embodiment 2 FIG. In the first embodiment, the fuel injection to the cylinder during the compression stroke is immediately terminated at the time of low pressure. However, if the fuel injection is not performed, the setting of the injection start time is canceled for the cylinder. May be. Hereinafter, with reference to the timing chart of FIG. 10 together with the configuration diagram of FIG. 1, the fuel injection valve according to the second embodiment of the present invention which cancels the setting of the injection start time for the cylinder in the compression stroke at low pressure. The control operation will be described.

In this case, the injection start time setting means in the ECU 15 (see FIG. 1) sets the fuel injection start time during the compression stroke when the fuel pressure is low, and sets the injection start time for the cylinder before fuel injection. In addition, the setting of the injection start time is canceled, and the supply of fuel is stopped until the next fuel injection starts.

FIG. 10 shows the first state when the fuel pressure is in the low pressure mode.
The control operation of the fuel injection valve 5 of the cylinder is shown in association with the crank angle signal CA, the stroke of the first cylinder, the fuel pressure mode, the compression stroke flag of the first cylinder, and the injection start flag. Further, tA, T1 and tAa are the same as described above.

First, at time tA, an injection start time T1 for opening the fuel injection valve 5 of the first cylinder at time tB2 is set in the injection start timer, and at the same time, an injection start flag is set. At this time, the fuel injection valve 5 of the first cylinder
The opening time is set to tB2.

Subsequently, at time tB1, the compression stroke flag of the first cylinder is set. At this time, since the fuel injection of the first cylinder has not been started even though the injection start flag of the first cylinder has been set, "0" is set in the injection start timer of the first cylinder and the fuel injection is immediately started. And immediately after that, the injection end timer of the first cylinder is set to “0” to immediately stop the fuel injection, and the injection start flag of the first cylinder is cleared. That is, substantially no fuel injection is performed at time tB1.

Further, the injection start time (see the broken line) set at time tB2 is canceled, and the fuel is not actually injected. As a result, the injection start timer in which the injection start time T1 is set at the time tA is canceled, and the fuel injection to the first cylinder during the compression stroke when the fuel pressure is low is prevented. The next injection start for the first cylinder is set at time tAa.

Embodiment 3 FIG. In the second embodiment, the setting of the injection start time is canceled for the cylinder before the fuel injection during the compression stroke at the time of low pressure.
The setting of the injection start time may be canceled for a cylinder before fuel injection during an explosion stroke at a high pressure. Hereinafter, together with the configuration diagram of FIG. 1 and the timing chart of FIG. 11,
A description will be given of a fuel injection valve control operation according to the third embodiment of the present invention, in which the setting of the injection start time is canceled for a cylinder in an explosion stroke at high pressure.

In this case, the injection start time setting means in the ECU 15 sets the fuel injection start time during the explosion stroke when the fuel pressure is high, and sets the injection start time for the cylinder before the fuel injection. The setting is released and the supply of fuel is stopped until the next fuel injection starts.

FIG. 11 shows a control operation of the fuel injection valve 5 of the first cylinder in the high pressure mode.
The stroke of the cylinder, the fuel pressure mode, the explosion stroke flag of the first cylinder, and the injection start flag are shown in association with each other. Further, tA, T1, tB1, tB2 and tAa are the same as described above.

First, at the time tA, the injection start time T1 is set so that the fuel injection valve 5 of the first cylinder is opened at the time tB2.
Is set in the injection start timer, and at the same time, the injection start flag is set. At this time, the time when the fuel injection valve 5 of the first cylinder opens is set to tB2.

Subsequently, at time tB1, the explosion stroke flag of the first cylinder is set. At this time, at the time tB1, the fuel injection of the first cylinder is not started even though the injection start flag of the first cylinder is set, so that the injection start timer of the first cylinder is set to “0”. Immediately after that, the fuel injection is started. Immediately thereafter, the injection end timer of the first cylinder is set to "0" to immediately stop the fuel injection, and the injection start flag of the first cylinder is cleared. That is, at time tB1, fuel injection is not substantially performed.

Further, the injection start time (see the broken line) set at time tB2 is canceled, and the fuel is not actually injected. As a result, the injection start timer in which the injection start time T1 is set at the time tA is canceled, and the fuel injection to the cylinder during the explosion stroke when the fuel pressure is low is prevented. The next start of injection for the first cylinder is set at time tAa.

Embodiment 4 FIG. (Corresponding to claims 7 and 9) In each of the above embodiments, the end of ignition was not considered, but if there is a cylinder that is injecting fuel at the end of ignition, it is desirable to immediately stop fuel injection. Hereinafter, a control operation according to the fourth embodiment of the present invention, which prevents fuel injection at the end of ignition, will be described with reference to the configuration diagram of FIG. 1 and the timing chart of FIG.

In this case, the injection end time setting means in the ECU 15 closes the fuel injection valve 5 and closes the next fuel injection to the cylinder in which the ignition plug 6 energized by the ignition timing control means is mounted and the fuel is being injected. The supply of fuel is stopped until the start of injection.

FIG. 12 shows the control operation of the fuel injection valve 5 for the first cylinder during fuel injection when the energization signal to the ignition plug 6 is turned off, and shows the crank angle signal CA, the stroke of the first cylinder, and the mounting on the first cylinder. The state is shown in association with the energized state of the ignition plug 6 and the injection start flag of the first cylinder. Further, tA to tD, T1, T2 and tAa are the same as described above.

First, at time tA, the injection start time T1 for opening the fuel injection valve 5 of the first cylinder at time tB is set in the injection start timer, and at the same time, the injection start flag is set. Subsequently, at time tB, the fuel injection valve 5 of the first cylinder is opened, and at the same time, the injection end time T2 for closing the fuel injection valve 5 of the first cylinder at time tD is set in the injection end timer. Clear the flag. At this time, the time at which the fuel injection valve 5 closes is tD.

On the other hand, at time tC, the energization of the ignition plug 6 mounted on the first cylinder is terminated.
Since the fuel injection valve 5 of the first cylinder is open, "0" is set to the injection end timer of the first cylinder and the fuel injection valve 5 is immediately closed. As a result, even if the fuel injection valve 5 of the first cylinder is opened during energization of the ignition plug 6, the fuel injection valve 5 is immediately closed when the energization of the ignition plug 6 is completed, so that fuel is not continuously injected after the energization is completed. The next injection start timing for the first cylinder is set at time tAa.

Here, the switching of the fuel pressure is not considered, but it is needless to say that the fuel pressure may be combined with the stop of the fuel in the compression stroke or the explosion stroke in the low pressure mode or the high pressure mode, and the same effect is obtained.

Embodiment 5 FIG. In the fourth embodiment, the fuel injection valve 5 is closed at the end of the ignition. However, the injection start time is set after the end of the ignition, and the fuel is injected into the cylinder before the fuel injection. The setting of the start time may be canceled. Hereinafter, a control operation according to the fifth embodiment of the present invention in which the setting of the injection start time after the end of the ignition is canceled to prevent the fuel injection will be described with reference to the timing chart of FIG. 13 together with the configuration diagram of FIG.

In this case, the injection start time setting means in the ECU 15 sets the fuel injection start time with the ignition plug 6 energized by the ignition timing control means attached and sets the injection start time to the cylinder before fuel injection. The setting of the start time is canceled and the supply of fuel is stopped until the next fuel injection starts.

FIG. 13 is a timing chart similar to FIG. 12, showing the control operation of the fuel injection valve 5 for the first cylinder before the injection when the injection start time is set when the energization signal to the ignition plug 6 is turned off. tA, tB1, tB2,
T1 and tAa are the same as described above.

First, at time tA, the injection start time T1 is set so that the fuel injection valve 5 of the first cylinder is opened at time tB2.
Is set in the injection start timer, and at the same time, the injection start flag is set. At this time, the time when the fuel injection valve 5 opens is set to tB2.

Subsequently, at time tB1, the ignition plug 6 of the first cylinder is de-energized. At this time, at the time tB1, the ignition of the first cylinder has ended, and the fuel injection of the first cylinder has not been started even though the injection start flag of the first cylinder has been set. The fuel injection start timer is set to "0" to immediately start the fuel injection. Immediately thereafter, the injection end timer of the first cylinder is set to "0" to immediately stop the fuel injection. Clear the start flag. That is, at time tB1, fuel injection is not substantially performed.

Further, the injection start time (see the broken line) set at time tB2 is canceled, and the fuel is not actually injected. As a result, at the time tA, the injection start timer in which the injection start time T1 is set is cancelled, and the fuel injection to the cylinder after the end of the ignition is prevented. The next injection start for the first cylinder is set at time tAa.

Although the switching of the fuel pressure is not considered here, it may be combined with the fuel stop in the compression stroke or the explosion stroke in the low pressure mode or the high pressure mode. In addition, although the above embodiments have been described individually, if the embodiments are arbitrarily combined, undesired fuel injection can be prevented with higher accuracy, so that a more reliable fuel for an in-cylinder injection type internal combustion engine can be obtained. It goes without saying that an injection valve control device can be realized.

[0121]

As described above, according to the first aspect of the present invention, a fuel injection valve for directly injecting fuel into each cylinder of an internal combustion engine and a spark plug for igniting fuel within each cylinder are provided. Fuel pressure switching means for switching the fuel pressure supplied to the fuel injection valve to low pressure or high pressure in accordance with the operation state of the internal combustion engine; crank angle detection means for detecting a crank angle of the internal combustion engine; In-cylinder having injection timing control means for controlling fuel injection timing according to a state and a crank angle, and ignition timing control means for controlling energization timing to a spark plug according to an operating state of an internal combustion engine and a crank angle In a fuel injection valve control system for an injection-type internal combustion engine , based on identification of piston top dead center
And a stroke identification means for identifying a cylinder in a compression stroke or an explosion stroke, and the injection timing control means responds to the switching state of the fuel pressure switching means and the stroke identification result to perform compression when the fuel pressure is low. Cylinders in the process
Has been designed to prohibit fuel injection in cylinders during the explosion stroke when the fuel pressure is high, so that regardless of the fuel injection pulse width, damage to the fuel injection valve and deterioration of exhaust gas can be prevented to improve reliability. There is an effect that an improved fuel injection valve control device for a direct injection internal combustion engine can be obtained.

According to a second aspect of the present invention, in the first aspect, the injection timing control means calculates an injection start time of fuel from a reference position of a crank angle in accordance with an operation state of the internal combustion engine. Start time calculation means, injection end time calculation means for calculating fuel injection end time from a reference position of the crank angle, an injection start timer for opening the fuel injection valve after a first predetermined time has elapsed, and a second An injection end timer for closing the fuel injection valve after a predetermined time has elapsed, an injection start time setting means for setting the injection start time to the injection start timer, and an injection end time setting means for setting the injection end time to the injection end timer And the process identification means includes:
Based on the crank angle and the top dead center of the specific cylinder, the cylinder in the compression stroke is identified, and the injection end time setting means sets the fuel in the compression stroke and the fuel in the fuel injection when the fuel pressure is low. Since the injection valve is closed and the supply of fuel is stopped until the start of the next fuel injection, fuel injection during the compression stroke at low fuel pressure can be prohibited even when the engine speed rises rapidly, and the fuel injection pulse Irrespective of the width, there is an effect that a fuel injection valve control device for a direct injection internal combustion engine with improved reliability by preventing damage to the fuel injection valve and deterioration of exhaust gas is obtained.

According to a third aspect of the present invention, in the first aspect, the injection timing control means calculates a fuel injection start time from a reference position of the crank angle in accordance with an operation state of the internal combustion engine. Start time calculation means, injection end time calculation means for calculating fuel injection end time from a reference position of the crank angle, an injection start timer for opening the fuel injection valve after a first predetermined time has elapsed, and a second An injection end timer for closing the fuel injection valve after a predetermined time has elapsed, an injection start time setting means for setting the injection start time to the injection start timer, and an injection end time setting means for setting the injection end time to the injection end timer And the process identification means includes:
Based on the crank angle and the top dead center of the specific cylinder, the cylinder in the explosion stroke is identified, and the injection end time setting means sets the fuel in the cylinder in the explosion stroke and during the fuel injection when the fuel pressure is high. Since the fuel supply is stopped until the next fuel injection is started while the injection valve is closed, fuel injection during the explosion stroke when the fuel pressure is high can be prohibited even when the engine speed rises rapidly. Irrespective of the width, there is an effect that a fuel injection valve control device for a direct injection internal combustion engine with improved reliability by preventing damage to the fuel injection valve and deterioration of exhaust gas is obtained.

According to a fourth aspect of the present invention, in the second aspect, the stroke identification means identifies a cylinder in an explosion stroke based on a crank angle and a top dead center of a specific cylinder, and determines an injection end time. When the fuel pressure is high, the setting means closes the fuel injection valve and stops the supply of fuel until the start of the next fuel injection to the cylinders during the explosion stroke and the fuel injection when the fuel pressure is high. Fuel injection during the compression stroke when the fuel pressure is low and the fuel injection during the explosion stroke when the fuel pressure is high, preventing fuel injection valve damage and deterioration of exhaust gas regardless of the fuel injection pulse width. Thus, there is an effect that a fuel injection valve control device for a direct injection internal combustion engine with improved reliability can be obtained.

According to claim 5 of the present invention, in claim 2 or claim 4, when the fuel pressure is low, the injection start time setting means is in the compression stroke and the fuel injection start time is set to For the cylinder set and before fuel injection,
The injection start time is canceled and the fuel supply is stopped until the next fuel injection starts.Therefore, even when the engine speed suddenly increases, regardless of the fuel injection pulse width, damage to the fuel injection valve or exhaust gas This has the effect of obtaining a fuel injection valve control device for a direct injection internal combustion engine in which reliability is improved by preventing deterioration of the fuel injection valve.

According to a sixth aspect of the present invention, in the third or fourth aspect, when the fuel pressure is high, the injection start time setting means is in an explosion stroke and the injection start time of the fuel is changed. For the cylinder set and before fuel injection,
The injection start time is canceled and the fuel supply is stopped until the next fuel injection starts.Therefore, even when the engine speed suddenly increases, regardless of the fuel injection pulse width, damage to the fuel injection valve or exhaust gas This has the effect of obtaining a fuel injection valve control device for a direct injection internal combustion engine in which reliability is improved by preventing deterioration of the fuel injection valve.

According to a seventh aspect of the present invention, in any one of the second to sixth aspects, the injection end time setting means is provided with a spark plug which has been de-energized by the ignition timing control means. Since the fuel injection valve is closed and the supply of fuel is stopped until the next fuel injection is started for the cylinder that is injecting fuel, the discharge of unburned gas can be prevented regardless of the fuel injection pulse width. This has the effect of providing a fuel injection valve control device for a direct injection internal combustion engine that has improved reliability by preventing damage to the fuel injection valve and deterioration of exhaust gas.

According to an eighth aspect of the present invention, in any one of the second to seventh aspects, the injection start time setting means is provided with a spark plug which has been de-energized by the ignition timing control means. Since the fuel injection start time is set and the injection start time is canceled for the cylinder before fuel injection and the supply of fuel is stopped until the next fuel injection starts, regardless of the fuel injection pulse width. It is possible to prevent the discharge of unburned gas, and it is possible to obtain a fuel injection valve control device for an in-cylinder injection type internal combustion engine that has improved reliability by preventing damage to the fuel injection valve and deterioration of the exhaust gas. .

According to a ninth aspect of the present invention, there is provided a fuel injection valve for directly injecting fuel into each cylinder of an internal combustion engine, a spark plug for igniting fuel in each cylinder, and an internal combustion engine. Crank angle detecting means for detecting the crank angle of
Injection timing control means for controlling the fuel injection timing according to the operating state and the crank angle of the internal combustion engine, and ignition timing control means for controlling the energization timing to the ignition plug according to the operating state and the crank angle of the internal combustion engine In a fuel injection valve control device for a direct injection internal combustion engine, a compression stroke is determined based on identification of a piston top dead center of a specific cylinder.
A stroke identification means for identifying a cylinder in a stroke or an explosion stroke ; and an injection timing control means for supplying electricity to a spark plug by an ignition timing control means based on a stroke identification result.
Is terminated and during the compression stroke or the explosion stroke , the fuel injection valve is closed and the supply of fuel is stopped until the start of the next fuel injection for the cylinder that is injecting fuel. Fuel injection valve control for a direct injection internal combustion engine with improved reliability by preventing the discharge of unburned gas regardless of the fuel injection pulse width and preventing damage to the fuel injection valve and deterioration of exhaust gas There is an effect that the device can be obtained.

According to a tenth aspect of the present invention, there is provided a fuel injection valve for directly injecting fuel into each cylinder of an internal combustion engine, a spark plug for igniting fuel in each cylinder,
Crank angle detecting means for detecting a crank angle of the internal combustion engine; injection timing control means for controlling fuel injection timing according to the operating state and the crank angle of the internal combustion engine; and ignition according to the operating state and the crank angle of the internal combustion engine In a fuel injection valve control apparatus for a direct injection internal combustion engine having an ignition timing control means for controlling a timing of energizing a plug, a pressure is determined based on identification of a piston top dead center of a specific cylinder.
A stroke identification means for identifying a cylinder in a contraction stroke or an explosion stroke is provided, and the injection timing control means controls the ignition timing to the ignition plug by the ignition timing control means based on the stroke identification result .
Is energized is terminated setting the injection starting time of the fuel and pressure
During the contraction stroke or the explosion stroke, for the cylinder before fuel injection , the setting of the injection start time is canceled and the supply of fuel is stopped until the next fuel injection, so regardless of the fuel injection pulse width. In addition, it is possible to prevent the discharge of unburned gas and to prevent the fuel injection valve from being damaged and the exhaust gas from deteriorating, thereby improving the reliability of the fuel injection valve control device for a direct injection internal combustion engine. is there.

[Brief description of the drawings]

FIG. 1 is a configuration diagram corresponding to Embodiments 1 to 5 of the present invention.

FIG. 2 is a flowchart showing a main routine of a fuel pressure setting operation according to the first embodiment of the present invention (corresponding to claims 1 to 4).

FIG. 3 is a flowchart showing a predetermined crank angle routine of a cylinder identification operation according to the first embodiment of the present invention.

FIG. 4 is a flowchart showing a predetermined crank angle routine of a cylinder identification operation according to the first embodiment of the present invention, continued from FIG. 3;

FIG. 5 is a flowchart showing a predetermined crank angle routine of a cylinder identification operation according to the first embodiment of the present invention, continued from FIG. 4;

FIG. 6 is a flowchart illustrating an injection start interrupt routine according to the first embodiment of the present invention.

FIG. 7 is a flowchart showing an ignition energizing signal off interrupt routine of a fuel injection valve control operation according to the first embodiment of the present invention.

FIG. 8 is a timing chart showing a fuel injection valve control operation according to the first embodiment of the present invention.

FIG. 9 is a timing chart showing a fuel injection valve control operation according to the first embodiment of the present invention.

FIG. 10 is a timing chart showing a fuel injection valve control operation according to a second embodiment (corresponding to claim 5) of the present invention.

FIG. 11 is a timing chart showing a fuel injection valve control operation according to a third embodiment (corresponding to claim 6) of the present invention.

FIG. 12 is a timing chart showing a fuel injection valve control operation according to a fourth embodiment (corresponding to claims 7 and 9) of the present invention.

FIG. 13 is a timing chart showing a fuel injection valve control operation according to a fifth embodiment (corresponding to claims 8 and 10) of the present invention.

FIG. 14 is a configuration diagram showing a conventional fuel injection valve control device for a direct injection internal combustion engine.

FIG. 15 is an enlarged sectional view showing the periphery of the fuel injection valve in FIG. 14;

FIG. 16 is an explanatory diagram showing an injection operation of a conventional fuel injection valve control device for a direct injection internal combustion engine.

[Explanation of symbols]

1 engine, 5 fuel injection valve, 6 spark plug, 7
High pressure fuel pump, 8 High pressure conduit, 9 Fuel tank, 10
Low pressure fuel pump, 11 Fuel pressure switching valve, 12
Low pressure regulator, 13 high pressure regulator, 14 crank angle sensor, 15 ECU, CA crank angle signal, tA reference position, tB injection start time, tB1 injection start time release time, tB2 set injection start time, tC actual Injection end time, tD Set injection end time, tAa Next reference position, T1 injection start time (first predetermined time), T2 Set injection end time (second predetermined time), Te from reference position Injection end time, S201 to S206, Step of switching fuel pressure, S307 Step of calculating fuel injection start time, S318 Step of setting injection start timer,
S319 Step of setting an injection start flag, S4
01, a step of identifying a cylinder, S402, a step of setting an injection end timer, S501, a step of determining fuel pressure, S502, a step of determining a compression stroke,
503 Step of determining an explosion stroke, S504 Step of determining an injection start flag, S505, S507
Determining a cylinder during fuel injection; step S506: setting an injection start timer to 0; step S508: setting an injection end timer to 0; and step S509: clearing an injection start flag.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI F02D 45/00 362 F02D 45/00 362D F02M 69/00 340 F02M 69/00 340R 340T (72) Inventor Takato Suetsugu Chiyoda Himeji-shi 840-cho, Himeji Works, Mitsubishi Electric Corporation (56) References JP-A-3-9050 (JP, A) JP-A-2-146253 (JP, A) JP-A-2-23250 (JP, A) Hei 5-86948 (JP, A) Japanese Utility Model 1-166270 (JP, U) Japanese Utility Model 63-78164 (JP, U) Japanese Utility Model 57-172052 (JP, U) (58) Field surveyed (Int) .Cl. ⁷ , DB name) F02D 41/00-41/40 F02D 43/00-45/00 F02B 1/00-23/10 F02M 39/00-71/04 F02D 17/02

Claims (10)

(57) [Claims] A fuel injection valve for injecting fuel directly into each cylinder of the internal combustion engine; a spark plug for igniting fuel in each of the cylinders; Fuel pressure switching means for switching a fuel pressure supplied to a fuel injection valve to low pressure or high pressure; crank angle detection means for detecting a crank angle of the internal combustion engine; and an operation state of the internal combustion engine and the crank angle according to the crank angle. An in-cylinder injection type internal combustion engine comprising: injection timing control means for controlling fuel injection timing; and ignition timing control means for controlling energization timing to the ignition plug according to the operating state of the internal combustion engine and the crank angle. In the fuel injection valve control device, the compression stroke is performed based on the identification of the top dead center of the piston of the specific cylinder.
Or stroke identifying means for identifying the cylinder that is in the explosion stroke is provided, wherein the injection timing control means is responsive to the switching state and the stroke identification result of the fuel pressure switching means, said fuel pressure
Cylinders during the compression stroke or when the force is low pressure
A fuel injection valve control device for an in-cylinder injection type internal combustion engine , wherein when a fuel pressure is high, fuel injection of a cylinder during the explosion stroke is prohibited. 2. An injection start time calculating means for calculating an injection start time of the fuel from a reference position of the crank angle in accordance with an operation state of the internal combustion engine; An injection end time calculating means for calculating an injection end time of the fuel from a position; an injection start timer for opening the fuel injection valve after a first predetermined time has elapsed; and An injection end timer for closing an injection valve; an injection start time setting unit for setting the injection start time in the injection start timer; and an injection end time setting unit for setting the injection end time in the injection end timer. The stroke identification means identifies a cylinder that is in a compression stroke based on the crank angle and the top dead center of the specific cylinder; 2. The cylinder according to claim 1, wherein when the fuel pressure is low, the fuel injection valve is closed and the supply of the fuel is stopped until the next fuel injection is started for a cylinder which is performing a compression stroke and fuel injection. Fuel injection valve control device for internal injection type internal combustion engine. 3. An injection start time calculating means for calculating an injection start time of the fuel from a reference position of the crank angle in accordance with an operation state of the internal combustion engine; An injection end time calculating means for calculating an injection end time of the fuel from a position; an injection start timer for opening the fuel injection valve after a first predetermined time has elapsed; and An injection end timer for closing an injection valve; an injection start time setting unit for setting the injection start time in the injection start timer; and an injection end time setting unit for setting the injection end time in the injection end timer. The stroke identification means identifies a cylinder in an explosion stroke based on the crank angle and the top dead center of the specific cylinder, and the injection end time setting means includes: 2. The cylinder according to claim 1, wherein when the fuel pressure is high, the fuel injection valve is closed and the supply of the fuel is stopped until the next fuel injection is started for a cylinder which is in an explosion stroke and is performing a fuel injection. Fuel injection valve control device for internal injection type internal combustion engine. 4. The stroke identification means identifies a cylinder in an explosion stroke based on the crank angle and the top dead center of the specific cylinder, and the injection end time setting means determines when the fuel pressure is high. 3. The cylinder-injected internal combustion engine according to claim 2, wherein the fuel injection valve is closed and the supply of the fuel is stopped until the next fuel injection is started for a cylinder that is undergoing an explosion stroke and is performing fuel injection. Fuel injector control device. 5. The injection start time setting means, wherein when the fuel pressure is low, the fuel injection start time is set during the compression stroke and the fuel injection start time is set for a cylinder before fuel injection. 5. The fuel injection valve control device for a direct injection internal combustion engine according to claim 2, wherein the setting is canceled and the supply of the fuel is stopped until the next fuel injection is started. 6. The fuel injection start time setting means, wherein when the fuel pressure is high, the fuel injection start time is set during the explosion stroke and the fuel before the fuel injection is set. 5. The fuel injection valve control apparatus for a direct injection internal combustion engine according to claim 3, wherein the setting is canceled and the supply of the fuel is stopped until the next fuel injection is started. 7. The fuel injection ending time setting means closes the fuel injection valve to a cylinder on which a spark plug, which has been energized by the ignition timing control means and is being injected, and is injecting fuel, and until the next fuel injection starts. The fuel injection valve control device for a direct injection internal combustion engine according to any one of claims 2 to 6, wherein the supply of the fuel is stopped. 8. The fuel injection start time setting means, wherein the fuel injection start time is set by mounting a spark plug energized by the ignition timing control means and the fuel injection start time is set for a cylinder before fuel injection. The fuel injection valve control device for a direct injection internal combustion engine according to any one of claims 2 to 7, wherein the setting of the time is canceled and the supply of the fuel is stopped until the next fuel injection is started. 9. A fuel injection valve for directly injecting fuel into each cylinder of the internal combustion engine, a spark plug for igniting fuel in each of the cylinders, and a crank angle for detecting a crank angle of the internal combustion engine Detection means; injection timing control means for controlling the fuel injection timing in accordance with the operating state of the internal combustion engine and the crank angle; energization of the ignition plug in accordance with the operating state of the internal combustion engine and the crank angle A fuel injection valve control device for a direct injection internal combustion engine having an ignition timing control means for controlling timing, wherein during a compression stroke based on identification of a piston top dead center of a specific cylinder ,
Alternatively, stroke identification means for identifying a cylinder in an explosion stroke is provided, and the injection timing control means uses the ignition timing control means to control the ignition plug based on the stroke identification result .
Is terminated and during the compression stroke or the explosion stroke
To the cylinder during the fuel injection be in a degree, a fuel injection valve control apparatus for a cylinder injection internal combustion engine, characterized in that closes the fuel injection valve to stop the supply of the fuel to the start of the next fuel injection . 10. A fuel injection valve for injecting fuel directly into each cylinder of the internal combustion engine, a spark plug for igniting fuel in each cylinder, and a crank angle for detecting a crank angle of the internal combustion engine Detecting means; injection timing control means for controlling the fuel injection timing according to the operating state of the internal combustion engine and the crank angle; energizing the ignition plug according to the operating state of the internal combustion engine and the crank angle A fuel injection valve control device for a direct injection internal combustion engine having an ignition timing control means for controlling a timing, wherein a compression stroke is performed based on identification of a piston top dead center of a specific cylinder.
Alternatively, stroke identification means for identifying a cylinder in an explosion stroke is provided, and the injection timing control means uses the ignition timing control means to control the ignition plug based on the stroke identification result .
And the fuel injection start time is set, and the setting of the injection start time is canceled for the cylinder before the fuel injection during the compression stroke or the explosion stroke .
Next fuel injection start to the fuel injection valve control apparatus for a cylinder injection internal combustion engine, characterized by stopping the supply of the fuel with that.