JP7424196B2 - engine equipment - Google Patents

Description

The present invention relates to an engine device.

Conventionally, as this type of engine device, one has been proposed that includes an engine having an in-cylinder injection valve that injects fuel into the inside of the combustion chamber and a spark plug installed near the top of the combustion chamber (for example, (See Patent Document 1). In this engine system, if knocking is detected during combustion mode operation in which fuel is injected from the in-cylinder injection valve during the compression stroke and stratified combustion is performed by forming a stratified mixture near the spark plug, the ignition timing is delayed. make a corner Further, when the amount of retardation of the fuel injection timing according to the ignition timing is smaller than the reference amount, fuel injection in the compression stroke is performed at the injection timing retarded according to the amount of retardation.

Japanese Patent Application Publication No. 2018-131948

In the above-mentioned engine devices, when warming up a purification device that has a catalyst that purifies exhaust gas, the ignition timing is generally retarded to supply more heat to the purification device, and the ignition timing is An expansion stroke may also be selected. In this case, it has been considered to perform fuel injection in synchronization with ignition in order to make ignition more reliable. Ignition during the expansion stroke can supply a large amount of heat to the purifier and warm it up quickly, so it is preferable to retard the ignition timing as much as possible, but the engine output torque is small. As a result, the engine speed tends to become unstable. For this reason, it becomes difficult to maintain the amount of retardation of the ignition timing in a favorable state.

The main purpose of the engine device of the present invention is to maintain the amount of retardation of ignition timing in a better state during warm-up of the purification device.

The engine device of the present invention employs the following means to achieve the above-mentioned main purpose.

The engine device of the present invention includes:
An engine having an in-cylinder injection valve that sprays fuel into a combustion chamber and a spark plug that can ignite the fuel sprayed from the in-cylinder injection valve;
a purification device having a purification catalyst that purifies the exhaust gas of the engine;
a control device that controls fuel injection by the in-cylinder injection valve and ignition by the spark plug;
An engine device comprising:
When warming up the purification device, the control device selects an expansion stroke injection warm-up in which the spark plug ignites during the expansion stroke and fuel is injected from the in-cylinder injection valve in synchronization with the ignition during the expansion stroke. and when you run it,
(A) When executing the expansion stroke injection warm-up using a predetermined base ignition timing as the ignition timing, if the engine speed is higher than the predetermined speed, the ignition timing is retarded and the engine speed is increased. Calculating the ignition timing by adding a correction value to the base ignition timing to advance the ignition timing when the rotation speed is lower than the predetermined rotation speed;
(B) reducing the intake air amount of the engine when the ignition timing is retarded by a predetermined retardation amount or more than the base ignition timing;
It is characterized by

In the engine device of the present invention, when warming up a purification device having a purification catalyst that purifies engine exhaust gas, ignition is performed by the spark plug during the expansion stroke, and fuel is ignited from the in-cylinder injector in synchronization with the ignition during the expansion stroke. When selecting and executing an expansion stroke injection warm-up that injects a The ignition timing is calculated by adding to the base ignition timing a correction value that retards the engine speed and advances the ignition timing when the engine speed is lower than a predetermined speed. Thereby, when the purification device is warmed up by expansion stroke injection warm-up, it is possible to maintain the retarded state of the ignition timing while stabilizing the rotational speed of the engine. Further, when the ignition timing is retarded by a predetermined retardation amount or more than the base ignition timing, the intake air amount of the engine is reduced. This makes it possible to prevent the ignition timing from retarding the base ignition timing by more than a predetermined retard amount. In this case, the range in which the ignition timing is up to the predetermined retardation amount from the base ignition timing functions as a dead zone, so hunting is caused by correcting the ignition timing depending on the engine speed and reducing the intake air amount of the engine by retarding the ignition timing. can be suppressed. As a result, the amount of retardation of the ignition timing can be maintained in a better state when the purifier is warmed up.

1 is a configuration diagram schematically showing the configuration of an engine device 10 as an example of the present invention. FIG. 2 is an explanatory diagram showing an example of changes over time in the rotational speed Ne of the engine 12 and the ignition timing Tf when expansion stroke injection warm-up is performed as rapid warm-up. 7 is a flowchart illustrating an example of expansion stroke injection warm-up feedback control executed by the ECU 70. FIG.

Next, a mode for carrying out the present invention will be described using examples.

FIG. 1 is a block diagram schematically showing the structure of an engine device 10 as an embodiment of the present invention. As illustrated, the engine device 10 of the embodiment includes an engine 12 and an electronic control unit (hereinafter referred to as "ECU") 70 that controls the engine 12. Note that this engine device 10 is installed in a car that runs using only the power from the engine 12, a hybrid car that includes a motor in addition to the engine 12, construction equipment that operates using the power from the engine 12, etc. . The embodiment will be described assuming that the engine device 10 is installed in an automobile.

The engine 12 is configured as an internal combustion engine that uses fuel such as gasoline or light oil to output power through four strokes: intake, compression, expansion, and exhaust. This engine 12 includes an in-cylinder injection valve 26 that injects fuel into a cylinder, and a spark plug 30. The in-cylinder injection valve 26 is disposed approximately at the center of the top of the combustion chamber 29, and injects fuel in a spray form. The spark plug 30 is arranged near the in-cylinder injection valve 26 so as to ignite the fuel sprayed from the in-cylinder injection valve 26. The engine 12 sucks air purified by the air cleaner 22 into the combustion chamber 29 through the intake pipe 25, and injects fuel from the in-cylinder injection valve 26 once or multiple times during the intake stroke or compression stroke. The electric spark from the ignition plug 30 causes explosive combustion, and the reciprocating motion of the piston 32 pushed down by the energy is converted into rotational motion of the crankshaft 16.

Exhaust gas discharged from the combustion chamber 29 of the engine 12 to the exhaust pipe 33 is purified by a purification catalyst (three-way catalyst) 34a that purifies harmful components such as carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx). It is discharged to the outside air through a purification device 34 having a

Although not shown, the ECU 70 is configured as a microprocessor centered on a CPU, and includes, in addition to the CPU, a ROM for storing processing programs, a RAM for temporarily storing data, and an input/output port. Signals from various sensors necessary to control the engine 12 are input to the ECU 70 via input ports. Signals input to the ECU 70 include, for example, the crank angle θcr from the crank position sensor 40 that detects the rotational position of the crankshaft 16, the cooling water temperature Tw from the water temperature sensor 42 that detects the temperature of the cooling water of the engine 12, Examples include cam angles θci and θco from the cam position sensor 44 that detects the rotational position of the intake camshaft that opens and closes the intake valve 28 and the rotational position of the exhaust camshaft that opens and closes the exhaust valve 31. In addition, the throttle opening TH from a throttle valve position sensor 46 that detects the position of the throttle valve 24 provided in the intake pipe 25, the intake air amount Qa from an air flow meter 48 attached to the intake pipe 25, The intake air temperature Ta from the temperature sensor 49 attached to the air intake pipe 25 and the intake pressure Pin from the intake pressure sensor 58 which detects the pressure inside the intake pipe 25 can also be mentioned. Further, the catalyst temperature Tc from the temperature sensor 34b that detects the temperature of the purification catalyst 34a of the purification device 34, the air-fuel ratio AF from the air-fuel ratio sensor 35a attached to the exhaust pipe 33, and the oxygen sensor attached to the exhaust pipe 33 are detected. The oxygen signal O2 from the cylinder block 35b and the knock signal Ks from the knock sensor 59 which is attached to the cylinder block and detects vibrations caused by the occurrence of knocking can also be mentioned.

Various control signals for controlling the engine 12 are output from the ECU 70 via an output port. Examples of the signals output from the ECU 70 include a drive control signal to the throttle motor 36 that adjusts the position of the throttle valve 24, a drive control signal to the in-cylinder injection valve 26, and a drive control signal to the spark plug 30. You can also do that.

The ECU 70 calculates the rotation speed Ne of the crankshaft 16, that is, the rotation speed Ne of the engine 12, based on the crank angle θcr from the crank position sensor 40. Further, the ECU 70 determines the volumetric efficiency as a load of the engine 12 (actually in one cycle with respect to the stroke volume per cycle of the engine 12) based on the intake air amount Qa from the air flow meter 48 and the rotation speed Ne of the engine 12. The ratio of the volume of air taken in) KL is also calculated.

In the engine device 10 configured in this manner, the ECU 70 controls intake air amount control, fuel injection control, and ignition control of the engine 12 so that the engine 12 is operated based on the target rotational speed Ne* and the target torque Te*. Let's do it. In the intake air amount control, the ECU 70 sets the target air amount Qa* based on the target torque Te* of the engine 12, and sets the target throttle opening TH* so that the intake air amount Qa becomes the target air amount Qa*. Then, the throttle motor 36 is controlled so that the throttle opening TH of the throttle valve 24 becomes the target throttle opening TH*. In the fuel injection control, the ECU 70 controls the target fuel injection of the in-cylinder injection valve 26 so that the air-fuel ratio AF becomes the target air-fuel ratio AF* (for example, the stoichiometric air-fuel ratio) based on the rotational speed Ne of the engine 12 and the volumetric efficiency KL. The amount Qfd* is set, and the in-cylinder injection valve 26 is controlled so that the target fuel injection amount Qfd* of fuel is injected from the in-cylinder injection valve 26 once or multiple times. In the ignition control, the ECU 70 sets a target ignition timing Tf* based on the rotational speed Ne of the engine 12 and the load factor KL, and controls the ignition coil 38 so that ignition is performed at the target ignition timing Tf*.

Next, the operation of the engine device 10 of the embodiment configured as described above, particularly the operation when rapidly warming up the purification catalyst (three-way catalyst) 34a of the purification device 34, will be described. Rapid warm-up of the purifying device 34 is performed when the condition that the catalyst temperature Tc is below a predetermined temperature below the activation temperature or the condition that the accelerator is turned off are satisfied. In rapid warm-up, when the water temperature Tw at the time of starting the engine 12 is lower than the first predetermined temperature (for example, 35 degrees or 45 degrees), fuel is injected 1 to 3 times during the intake stroke to warm up the catalyst more quickly. The final fuel injection is performed during the expansion stroke in order to improve the engine's performance and improve emissions, and is performed by expansion stroke injection warm-up, which is ignited in synchronization with the fuel injection during the expansion stroke. On the other hand, when the water temperature at the time of starting the engine 12 is higher than the first predetermined temperature, the final fuel injection is performed in the compression stroke and ignited in the expansion stroke to maintain good emissions. During the expansion stroke injection warm-up, the ignition timing Tf is controlled to be delayed as much as possible. If the ignition timing Tf is retarded, the combustion efficiency will decrease, so the rotational speed Ne of the engine 12 is maintained by increasing the amount of intake air. As a result, since the amount of combustion gas increases, the absolute amount of emission components also increases, but catalyst warm-up is accelerated. In the compression stroke injection warm-up, the catalyst is warmed up while maintaining good emissions, so the amount of retardation of the ignition timing Tf is smaller than in the expansion stroke injection warm-up. In the embodiment, depending on whether expansion stroke injection warm-up or compression stroke injection warm-up is selected, the base ignition timing Tfbase as the base value of the ignition timing Tf and the rotation speed Ne of the engine 12 are set for warm-up. In order to maintain the rotational speed Neset (for example, 1300 rpm, 1500 rpm, etc.), the feedback correction value Tk for correcting the amount of retardation of the ignition timing Tf and the retard side guard value Tfgrd are changed. Therefore, the base ignition timing Tfb1 and retard side guard value Tfg1 during expansion stroke injection warm-up and the base ignition timing Tfb2 and retard side guard value Tfg2 during compression stroke injection warm-up are determined in advance and stored as a map. However, when expansion stroke injection warm-up is selected, base ignition timing Tfb1 and retard side guard value Tfg1 are set and used as base ignition timing Tfbase and retard side guard value Tfgrd from the map, and compression stroke injection warm-up is selected. When the base ignition timing Tfb2 and the retard side guard value Tfg2 are set as the base ignition timing Tfbase and the retard side guard value Tfgrd from the map, the base ignition timing Tfb2 and the retard side guard value Tfgrd are used. Note that ATDC20 (After TDC (Top Dead Center) 20 degrees) or ATDC18 can be used as the base ignition timing Tfb1 during expansion stroke injection warm-up, and 3 as the retard side guard value Tfg1. Degrees, fifth degrees, etc. can be used. In addition, the base ignition timing Tfb2 during compression stroke injection warm-up is on the advanced side compared to the base ignition timing Tfb1 during expansion stroke injection warm-up, and for example, ATDC10 or ATDC15 can be used. As the value Tfg2, 3 degrees, 5 degrees, etc. can be used.

Further, rapid warm-up is performed when the shift position is the neutral position (N position) and when the shift position is the drive position (D position). In the embodiment, the above-mentioned first predetermined temperature is switched depending on the shift position. That is, the water temperature Tw at the time of starting the engine 12, which determines whether expansion stroke injection warm-up or compression stroke injection warm-up is selected depending on the shift position, switches the first predetermined temperature. For example, in the N position, 45 degrees is used as the first predetermined temperature, and in the D position, 35 degrees is used as the first predetermined temperature. Warming up may be made easier to select.

When rapid warm-up is performed at high altitudes, the output torque of the engine 12 decreases due to the lower air density. Correct Tfbase to the advance side.

FIG. 2 is an explanatory diagram showing an example of changes over time in the rotational speed Ne of the engine 12 and the ignition timing Tf when expansion stroke injection warm-up is performed as rapid warm-up. In the ignition timing Tf of FIG. 2, the lower side is shown as a retarded side and the upper side is shown as an advanced side. When the rapid warm-up execution condition is met at time T1, a process is started in which the engine speed Ne of the engine 12 is increased to the warm-up speed Neset and the ignition timing Tf is slowly retarded. At time T2 when the rotational speed Ne of the engine 12 reaches the warm-up rotational speed Neset, processing is performed to relatively quickly retard the ignition timing Tf while maintaining the rotational speed Ne of the engine 12 at the warm-up rotational speed Neset. Start. From the time T3 when the ignition timing Tf is retarded to the base ignition timing Tfbase, the amount of retardation of the ignition timing Tf is maintained in a better state while maintaining the rotational speed Ne of the engine 12 at the warm-up rotational speed Neset. Implement tension stroke injection warm-up feedback control to achieve this. This control will be described later. When the warm-up end transition condition is satisfied at time T4, a process is started for relatively quickly advancing the ignition timing Tf while maintaining the engine 12 rotation speed Ne at the warm-up rotation speed Neset. Warm-up completion transition conditions include conditions where the catalyst temperature Tc is equal to or higher than the activation temperature, conditions where the cooling water temperature Tw of the engine 12 is equal to or higher than a second predetermined temperature (for example, 70 degrees, etc.), and the cumulative intake air amount is equal to or higher than a predetermined amount. Any one or more of the above conditions, the condition that the accelerator is turned on, etc. can be used. Then, at time T5 when the ignition timing Tf reaches the end determination ignition timing Tfend, the expansion stroke injection is ended, and the ignition timing Tf is gradually changed to the target ignition timing Tf* that is set after the end of rapid warm-up. At this time, the rotation speed Ne of the engine 12 is adjusted to the target rotation speed Ne* that is set after the rapid warm-up is completed. In FIG. 2, the rotation speed Ne of the engine 12 is set to the idle rotation speed, assuming that the warm-up of the purification device 34 is completed. Note that the compression top dead center (TDC) or a value slightly retarded than the compression top dead center (TDC) can be used as the end determination ignition timing Tfend. At time T6 when the ignition timing Tf reaches the target ignition timing Tf*, the rapid warm-up is completely completed and the ignition timing Tf reaches the normal ignition timing Tf in which the engine 12 outputs torque according to the accelerator opening.

Next, expansion stroke injection warm-up feedback control will be explained. FIG. 2 is a flowchart illustrating an example of expansion stroke injection warm-up feedback control executed by the ECU 70. The expansion stroke injection warm-up feedback control adjusts the ignition timing Tf based on the rotational speed Ne of the engine 12 and adjusts the ignition timing Tf based on the amount of retardation of the ignition timing Tf from the base ignition timing Tfbase until the warm-up end transition condition is satisfied. This is feedback control that adjusts the intake air amount. The repetition frequency of the expansion stroke injection warm-up feedback control is the frequency of repeating the calculation of the ignition timing Tf. For example, in the case of a 4-cylinder engine, it is the frequency of every 180 degrees of crank angle, and in the case of a 6-cylinder engine, it is every 180 degrees of crank angle. The frequency is every 120 degrees.

When the expansion stroke injection warm-up feedback control is executed, the ECU 70 first inputs the rotation speed Ne of the engine 12 (step S100), and calculates the difference (Ne -Neset), an ignition timing correction value Tk in feedback using a proportional term and an integral term is calculated (step S110). Then, the ignition timing Tf is calculated by adding the ignition timing correction value Tk to the base ignition timing Tfbase (step S120). Thereby, the ignition timing Tf can be retarded while maintaining the rotation speed of the engine 12 at the warm-up rotation speed Nset.

Next, an intake air amount correction value Qk in feedback using an integral term is calculated for the ignition timing correction value Tk in feedback of the ignition timing Tf (step S130). The reason why the intake air amount correction value Qk is calculated using an integral term without using a proportional term is to suppress hunting caused by coexisting feedback control of the ignition timing Tf and feedback control of the intake air amount Qa. Subsequently, it is determined whether the ignition timing correction value Tk is greater than or equal to the threshold value Tfref (step S140). The threshold value Tfref sets a dead zone from the base ignition timing Tfbase, and can be, for example, 3 degrees or 4 degrees. When it is determined that the ignition timing correction value Tk is greater than or equal to the threshold value Tfref, the intake air amount Qa is reduced by the intake air amount correction value Qk (step S150). Specifically, the intake air amount Qa is reduced by closing the throttle valve 24 by the amount expected to reduce the intake air amount Qa by the intake air amount correction value Qk. As a result, the rotational speed Ne of the engine 12 decreases, so the next time this expansion stroke injection warm-up feedback control is executed, the ignition timing correction value Tk of the feedback of the ignition timing Tf based on the rotational speed Ne of the engine 12 is calculated to be smaller. will be done. In this way, when the intake air amount Qa is reduced by the intake air amount correction value Qk, or when it is determined in step S150 that the ignition timing correction value Tk is less than the threshold value Tfref, it is determined whether the warm-up end transition condition is satisfied. (Step S160), when it is determined that the warm-up end transition condition is not satisfied, the process returns to the process of reading the rotational speed Ne of the engine 12 in the first step S100 of the repeated process in the expansion stroke injection warm-up feedback control. On the other hand, when it is determined in step S160 that the warm-up end transition condition is satisfied, the expansion stroke injection warm-up feedback control is ended.

While the expansion stroke injection warm-up feedback control is being executed, the temperature of the engine 12 increases as time passes, so the friction torque decreases and the rotational speed Ne of the engine 12 increases, causing the warm-up rotation. The number will exceed the number Neset. At this time, the ignition timing Tf is retarded by feedback control of the ignition timing Tf based on the rotation speed Ne of the engine 12, and the rotation speed Ne of the engine 12 is returned to the warm-up rotation speed Neset. When the ignition timing correction value Tk, which is the amount of retardation of the ignition timing Tf from the base ignition timing Tfbase, exceeds the threshold value Tfref, the intake based on the amount of retardation of the ignition timing Tf from the base ignition timing Tfbase (ignition timing correction value Tk) Feedback control of the air amount Qa reduces the intake air amount Qa by the intake air amount correction value Qk. As a result, the rotation speed Ne of the engine 12 falls from the warm-up rotation speed Neset, the ignition timing Tf is advanced by feedback control of the ignition timing Tf based on the rotation speed Ne of the engine 12, and the rotation speed Ne of the engine 12 is increased. The rotation speed is returned to the warm-up rotation speed Neset. In this way, the rotational speed Ne of the engine 12 is maintained at the warm-up rotational speed Neset, and the ignition timing Tf is maintained well within the retardation range from the base ignition timing Tfbase to the threshold value Tfref. In feedback control of the intake air amount Qa based on the amount of retardation of the ignition timing Tf from the base ignition timing Tfbase (ignition timing correction value Tk), by providing a dead zone and calculating the intake air amount correction value Qk only using an integral term. , suppresses hunting that may occur due to the coexistence of feedback control of the ignition timing Tf based on the rotational speed Ne of the engine 12 and feedback control of the intake air amount Qa based on the amount of retardation of the ignition timing Tf (ignition timing correction value Tk). do.

In the engine device 10 of the embodiment described above, during expansion stroke injection warm-up, feedback control of the ignition timing Tf based on the rotation speed Ne of the engine 12 and retardation amount (ignition Expansion stroke injection warm-up feedback control that coexists with feedback control of the intake air amount Qa based on the timing correction value Tk) is executed. Thereby, the amount of retardation of the ignition timing Tf can be maintained satisfactorily while maintaining the rotational speed Ne of the engine 12 at the warm-up rotational speed Neset. In addition, in the feedback control of the intake air amount Qa based on the amount of retardation of the ignition timing Tf from the base ignition timing Tfbase (ignition timing correction value Tk), a dead zone is provided and the intake air amount correction value Qk is calculated using only an integral term. As a result, hunting may occur due to the coexistence of feedback control of the ignition timing Tf based on the rotational speed Ne of the engine 12 and feedback control of the intake air amount Qa based on the retardation amount of the ignition timing Tf (ignition timing correction value Tk). can be suppressed. As a result, the ignition timing Tf can be satisfactorily maintained within the retardation amount range from the base ignition timing Tfbase to the threshold value Tfref while maintaining the rotational speed Ne of the engine 12 at the warm-up rotational speed Neset.

In the engine device 10 of the embodiment, feedback control of the intake air amount Qa is performed based on the retardation amount (ignition timing correction value Tk) of the ignition timing Tf from the base ignition timing Tfbase when the ignition timing correction value Tk is greater than or equal to the threshold value Tfref. It is assumed that the intake air amount Qa is reduced by the intake air amount correction value Qk. However, when the absolute value of the ignition timing correction value Tk as a negative value (advance side) is greater than or equal to the threshold value Tfref (as a negative value, it is less than or equal to the threshold value Tfref), the intake air amount Qa is reduced by the intake air amount correction value Qk. It may be increased. That is, the intake air amount Qa may be controlled to be increased or decreased when the ignition timing Tf is greater than or equal to the plus or minus threshold value Tfref with respect to the base ignition timing Tfbase.

In the engine device 10 of the embodiment, as feedback control of the intake air amount Qa based on the amount of retardation of the ignition timing Tf from the base ignition timing Tfbase (ignition timing correction value Tk), the ignition timing correction value Tk is set to a threshold value Tfref that functions as a dead zone. In the above case, the intake air amount Qa is reduced by the intake air amount correction value Qk. However, such a dead zone may not be used.

In the engine device 10 of the embodiment, in feedback control of the intake air amount Qa based on the amount of retardation of the ignition timing Tf from the base ignition timing Tfbase (ignition timing correction value Tk), the intake air amount correction value Qk is controlled only by an integral term. I decided to calculate it. However, the intake air amount correction value Qk may be calculated using a proportional term and an integral term.

The engine device 10 of the embodiment may be mounted, for example, in an automobile equipped with an automatic transmission in the rear stage, or may be mounted in a hybrid automobile together with a motor that outputs driving power.

The correspondence between the main elements of the embodiments and the main elements of the invention described in the column of means for solving the problems will be explained. In the embodiment, the engine 12 corresponds to an "engine," the purification device 34 corresponds to a "purification device," and the ECU 70 corresponds to a "control device."

The correspondence relationship between the main elements of the examples and the main elements of the invention described in the column of means for solving the problem is that the example implements the invention described in the column of means for solving the problem. Since this is an example for specifically explaining a form for solving the problem, it is not intended to limit the elements of the invention described in the column of means for solving the problems. In other words, the interpretation of the invention described in the column of means for solving the problem should be based on the description in that column, and the examples are based on the description of the invention described in the column of means for solving the problem. This is just one specific example.

Although the embodiments of the present invention have been described above using examples, the present invention is not limited to these examples in any way, and may be modified in various forms without departing from the gist of the present invention. Of course, it can be implemented.

INDUSTRIAL APPLICATION This invention can be utilized for the manufacturing industry of an engine device, etc.

Reference Signs List 10 engine device, 12 engine, 16 crankshaft, 22 air cleaner, 24 throttle valve, 25 intake pipe, 26 in-cylinder injection valve, 34b temperature sensor, 28 intake valve, 29 combustion chamber, 30 spark plug, 31 exhaust valve, 32 piston , 33 exhaust pipe, 34 purification device, 34a purification catalyst, 35a air-fuel ratio sensor, 35b oxygen sensor, 36 throttle motor, 40 crank position sensor, 42 water temperature sensor, 44 cam position sensor, 46 throttle valve position sensor, 48 air flow meter, 49 temperature sensor, 58 intake pressure sensor, 59 knock sensor, 70 electronic control unit.

Claims (1)

An in-cylinder injection valve that is arranged approximately at the center of the top of a combustion chamber and injects fuel into the combustion chamber in a spray form; and a cylinder injection valve that is arranged near the in-cylinder injection valve and that injects fuel in a spray form from the in-cylinder injection valve. an engine having a spark plug capable of igniting;
a purification device having a purification catalyst that purifies the exhaust gas of the engine;
a control device that controls fuel injection by the in-cylinder injection valve and ignition by the spark plug;
An engine device comprising:
When warming up the purification device, the control device selects an expansion stroke injection warm-up in which the spark plug ignites during the expansion stroke and fuel is injected from the in-cylinder injection valve in synchronization with the ignition during the expansion stroke. and when you run it,
(A) When executing the expansion stroke injection warm-up using a predetermined base ignition timing as the ignition timing, if the engine speed is higher than the predetermined speed, the ignition timing is retarded and the engine speed is increased. Calculating the ignition timing by adding a correction value to the base ignition timing to advance the ignition timing when the rotation speed is lower than the predetermined rotation speed;
(B) reducing the intake air amount of the engine when the correction value reaches a predetermined retard amount or more on the retard side ;
An engine device characterized by:

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